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黑龙江省哈尔滨市第六中学2009届高三第一次模拟考试

英语试题

I.          听力

第一节(共5小题;每小题1.5分,满分7.5分)

1. Why cannot Nancy answer the phone?

A. She’s on the way to office right now.

B. She’s answering another phone call.

C. She’s out to buy some lines.

2. What does the woman mean?

A. She is willing to let the man use her dictionary.

B. She doesn’t think the man needs the dictionary.

C. She wonders why the man wants to use her dictionary.

3. How many books can the man borrow?

A. Twenty-five    B. Five     C. Twenty

4. Where is Mr. Wang now?

  A. In America     B. In Japan   C. In his company

5. What will the woman have to do?

  A. Use the tape herself  B. Keep the tape for another week

  C. Return the tape to the man.

第二节(共15小题;每小题1.5分,满分22.5分)

听第6段材料,回答第6至8题。

6. What is the probable relationship between the two speakers?

  A. Doctor and patient   B. Lawyer and client 

C. Receptionist and patient

7. What is the man’s problem?

  A. He has a stomachache   B. He has chest pains 

C. He has a sore throat

8. When is the man going to Dr. Black’s office?

  A. Right away   B. In the afternoon   C. At ten in the morning

听第7段材料,回答第9至11题。

9. Why does the man want to find a nurse?

  A. He likes the nurse to chat with his parents

  B. His mother wants a nice nurse to help her

  C. He needs a nurse to look after his sick father

10. What do you know about the man?

  A. He never thought it’s so difficult to find a nurse.

  B. He doesn’t want his mother herself to take care of his father

  C. He cares more about his father than about his mother

11. What can be inferred from the conversation?

  A. The man’s mother used to be a nurse

  B. The man’s father has been in hospital for a long time.

  C. The man has interviewed several nurses.

听第8段材料,回答第12至14小题。

12. What may be the man’s purpose according to the conversation?

  A. He wants to find a suitable job.   B. He wants to get a girlfriend.

  C. He wants to marry the woman.

13. What kind of people might the man prefer?

  A. A serious person   B. A practical person  C. A rich person

14. What’s the man’s possible favor according to the conversation?

  A. Sightseeing   B. Running a restaurant  C. Writing

听第9段材料,回答第15至17题。

15. Why does the woman want to travel after graduation?

  A. To enrich her experience  B. To find a good job while traveling

  C. To see different places described in the books

16. How can we adapt to the changing environment according to the woman?

  A. We should be independent    B. We should be willing to change

  C. We should get to know different people.

17. What will the woman learn while traveling?

  A. To help people   B. To believe herself  C. To value people

听第10段材料,回答第18至20题。

18. How will buyers pay for items they have chosen on TV?

  A. By making a phone call   B. By charging them to a credit card

  C. By paying for them at the cashier’s.

19. Why do some people prefer to shop in stores?

  A. It’s taken as a way to relax     B. They can shop around the clock

  C. Goods in store is a bit cheaper

20. What can you infer from the text?

  A. Store shopping will be replaced in the future.

  B. Store shopping and home shopping are needed by different people.

  C. Shopping on the Internet is developing rapidly.

II. 单项选择

21. It is known that water is not _____ endless resource, nor _____ that can be made once more.

   A. the; 不填      B. an; one       C. an; that         D. 不填;one

22. I’m not sure whether I will have anything else to do tomorrow. ____,I will try every possible means to come to the party.

   A. Even though    B. Anyhow    C. If so    D. Instead

23. It is required that the students ______ mobile phones in their school, so seldom ____ them using one.

   A. not use; will you see    B. should not use; you will see

   C. don’t use; will you see   D. not use; you will see

24. With the electric map ______ in the car _____ the exact position, the driver can drive in the right direction of the destination.

A. fixing; showing        B. fixed; shown

C. fixed; showing         D. fixing; shown

25. ?When did you last hear ____ Jay?

   --He phoned me this morning, and we agreed____ a time and place to meet.

   A. of; to    B. about; with   C. from; with   D. from; on

26. ―Tom has missed yesterday’s class, so ____ one example is necessary to get him to grasp this rule clearly.

27. He spent at least as much time reading as you____ online yesterday.

   A. had to chat   B. do chatting   C. had chatted   D. did chatting

28. ?Do the students learn any foreign language in your school?

   - Yes, more than one____ taught in this school.

   A. language is   B. language are   C. language be  D. languages are

29. It’s hard for him to play against me. I’ve got nothing to play for, but for him, he needs to win so ______.

   A. far    B. well    C. little     D. badly

30. ---You seem to get lost. Need help?

   --- _______.

   A. Yes, give me a hand, please.

   B. Help me find my bag, please.

   C. I’m looking for the No.1 bus.

   D. Yes, would you please help me with the bag?

31. As the light turned green, I stood for a moment, not ____, and asked myself what I was going to do.

   A. moved   B. moving    C. to move     D. being moved

32. Without proper lessons, you could ____ a lot of bad habits when playing the piano.

   A. give up   B. catch up    C. keep up    D. pick up

33. At the sight of the policeman, ___from behind the door.

   A. did the boy rush out   B. did he sit down  

C. out rushed the boy    D. rushing out was the boy

34. He often speaks of the trouble he _____ to help the orphan.

   A. had     B. found   C. made    D. took

35. ---We didn’t find the Blacks ____ the lecture.

   ---No one had told them about _____ a lecture the following day.

   A. to attend; there to be      B. attending; there being

   C. attended; there be         D. attend; there was

III. 完形填空 

I think the most basic and powerful way to connect to another person is to listen. Perhaps, the most important thing we ever give each other is our  36 , and especially if it’s given from our hearts.

   When people are talking,  37  is no need to do anything but  38  them and take them in. Listen to what they are  39 . In most cases,  40  is more important than understanding. It has taken me a long time to believe in the  41  of simple saying “ I’m so sorry ” when some one is in pain.

   One of my patients told me that when she tried to tell her story, people often  42  her to tell her that they once had  43  just like what happened to her. Finally, she  44  talking to most people.

45 , we connect to each other through listening. When we interrupt what someone is saying to let him or her know that we understand, we move the focus of attention to ourselves.

I have  46  learned to respond to someone’s  47  by just listening to him or her. In the old days, I used to  48 the tissue (纸巾). I realized that passing a person a tissue  49  be just another way to  50  them down and take them out of their experience of  51 . Now just listen. When they have cried all they  52  to cry, they find me there with them.

This simple thing has not been that easy to learn. It certainly went  53  everything I had been taught since I was very young. I  54  think that people listened only because they did not know the answer. But now I know that a loving  55  often has more power to comfort others than words.

36.

A. attention

B. love

C. minds

D. actions

37.

A. it

B. that

C. this

D. there

38.

A. receive

B. accept

C. get

D. bring

39.

A. speaking

B. talking

C. telling

D. saying

40.

A. discussing

B. doing

C. listening

D. hearing

41.

A. effort

B. power

C. treasure

D. strength

42.

A. interrupted

B. disturbed

C. asked

D. demanded

43.

A. everything

B. anything

C. something

D. nothing

44.

A. began

B. stopped

C. started

D. continued

45.

A. In fact

B. At length

C. As a result

D. In other words

46.

A. still

B. never

C. even

D. hardly

47.

A. anxiety

B. laughing

C. shouting

D. crying

48.

A. give off

B. reach for

C. reach out

D. give up

49.

A. might

B. will

C. had to

D. must

50.

A. break

B. put

C. pull

D. calm

51.

A. happiness

B. sadness

C. anger

D. delight

52.

A. try

B. manage

C. need

D. like

53.

A. against

B. for

C. out

D. with

54.

A. always

B. happened to

C. seldom

D. used to

55.

A. lecture

B. understanding

C. silence

D. act

IV. 阅读理解

A

  I was doing some Christmas shopping in a toy store and decided to look at Barbie dolls for my nieces. A nicely dressed little girl was excitedly looking through the Barbie dolls as well. As she was looking, a little boy came to the Pokemon toys. He was dressed neatly, but his clothed were obviously old. He was with his father as well, and kept picking up the Pokemon video toys. Each time he picked one up and looked at his father, his father shook his head and said, “No.”

  The little girl had chosen her Barbie. However, she stopped and was watching them. Rather dejectedly, the boy had to give up the Pokemon toys and choose something else. The little girl put her Barbie back on the shelf, and ran over to the Pokemon toys. She excitedly picked up one and raced towards the checkout. I picked up my purchases and got in line behind them. Then, much to the little girl’s delight, the little boy and his father got in line behind me. After the toy was paid for and bagged, the little girl handed it back to the cashier (收银员) and whispered something in her ear. The casher smiled and put the package under the counter.

  I paid for my purchases and was rearranging things when the little boy came up to the cashier. The cashier checked his purchases and said, “Congratulations, you are my hundredth customer today, and you win a prize!” With that, she handed the little boy the Pokemon toys, and he could only stare in surprise. It was exactly what he had wanted!

  The little girl and her father had been standing at the doorway during all of this. Then they walked out. As I walked back to my car, I heard the father ask his daughter why she had done that. I’ll never forget what she said to him. “Daddy, didn’t Grandparents want me to buy something that would make me happy?” He said, “Of course they did, honey.” To which the little girl replied, “ Well, I just did!”

  I feel very shocked to have witnessed the true spirit of Christmas in that boy store, in the form of a little girl who understands more about the meaning of this festival than most adults I know.

56. The underlined word “dejectedly” in the second paragraph probably means _____.

   A. delightedly  B. disappointedly  C. excitedly   D. unexpectedly

57. How did the little boy get the Pokemon toys?

   A. His father bought him the Poknemon toys.

   B. Fortunately, he was the hundredth customer and won the Poknemon toys.

   C. The cashier felt sympathy for the little boy and gave him the Poknemon toys.

   D. The little girl bought the Poknemon toys for him.

58. What did the little girl mean when saying “Daddy, didn’t Grandparents want me to buy something that would make me happy?”

   A. Her Grandparents wanted her to be happy.

   B. Making the little boy happy made her happy.

   C. The Poknemon toys made her happy.

   D. Her Grandparents hoped that she could help others.

59. Which of the following statements is NOT true according to the passage?

   A. the story happened before Christmas.

   B. The little boy had no enough money to buy the Poknemon toys.

   C. Although the little girl liked the Poknemon toys very much, she gave them to the boy.

   D. The author was deeply moved by the behavior of the little girl.

                             B

The day after Thanksgiving is considered the first day of the holiday shopping season in the United States. It even has a name ― “Black Friday.” The name comes from the idea that this is the day when store owners begin to show a profit for the year.

In the past, before calculators and computers, workers recorded the profits and losses of American businesses in special books. They used red ink to record losses. They used black ink to record profits. They used the term “in the red” to mean losing money. “In the black” meant making a profit. So “Black Friday” was the day when the store owners moved from being “in the red” to “in the black.”

Many people consider “Black Friday” to be the busiest shopping day of the year. But that is probably false. Researchers say it may be the day when the largest number of people go to stores. But it is not necessarily the day when shoppers spend the largest amount of money. Some experts say Americans just want to get out of the house the day after Thanksgiving. And many stores reduce some of their prices on “Black Friday.” 

However, experts say that many people wait until much closer to Christmas, December 25, hoping to find even lower prices. They say the busiest day of the year in terms of the amount of shoppers and sales is usually the Saturday before Christmas.

A marketing services company carried out a public opinion study about shopping last month. It asked almost one thousand Americans about their gift buying plans. One-third said they plan to go to stores to shop on the day after Thanksgiving.

The study found that these shoppers are mainly young people, probably because older people do not want to deal with huge crowds. In fact, business leaders say many older Americans are doing their shopping at home -- on the computer. They say the day most people shop online is the Monday after “Black Friday.” They even have a name for it -- “Cyber Monday.” 

60. Which is the busiest shopping day of the year according to the text?

A. Black Friday

B. the day before Christmas

C. the Saturday before Christmas

D. Cyber Monday

61. Which of the following is true according to the passage?

A. Businessmen prefer the term “in the red” to “in the black”.

B. “Black Friday” means store owners begin to earn money.

C. The largest amount of sales is made on “Black Friday”.

D. The largest number of people go to stores on “Black Friday”.

62. Why don’t people spend money on “Black Friday”?

A. They are not satisfied with the quality of the goods sold.

B. Some shops secretly increase their prices on that day.

C. Too many people in the store discourage their shopping desire.

D. They are waiting for a more competitive price.

63. From the passage we can conclude that ________.

A. Stores failed to earn much money from older people on “Black Friday”.

B. “Cyber Monday” has a larger amount of sales than “Black Friday”.

C. All young people prefer going to stores on “Black Friday”.

D. Older people like shopping on-line because of cheaper prices.

 

C

  The following are the results of the tests done by “Family and Home Magazine” on some Pocket Tape-Recorders on the market now.

  Pearlcorder S702 $64

  This simple model at the bottom of the Olympus range scored the most points for its excellent quality of recording. Background noise hardly affects the sound and recording from a pocket is perfectly possible, but it doesn’t turn off automatically.

  Tape length: 30minutes per side. Weight: 240g.

  Sony M9   $49.95

  Small and very good looking, Sony’s latest offering scored most for its appearance. Sounds clear, but there is slight machine noise. The big control buttons are a great improvement on some of the complicated little controls on other tape-recorders. It doesn’t switch off automatically, but a red light shows if the machine is still running.

  Tape length: 60minutes per side. Weight: 195g.

  Sony M400  $115

  Lots of little control buttons that make a noise are difficult to use. Recording is good but machine noise loses points. Tape counter and automatic switch-off when tape has finished recording or rewinding are useful.

  Tape length: 60 minutes per side. Weight: 230g.

  Imperial OEM MC7  $ 29.95

  Cheap and simple compared with the rest, but recording is good as long as there is no background noise. Use only its own-make of cassette. No light to show it is on; no fast-forward button and the record button makes a loud noise.

  Tape length: 30 minutes per side. Weight: 285g.

  Philips 585  $80

  Handsome and simple to use, but recording is very poor at more than the recommended distance of 5 cm-designed for dictation. No recording light.

  Tape length: 15 minutes per side. Weight: 220g.

64. The machine that produces the best recording with the least unwanted noise is __.

   A. Pearlcorder S 702     B. Sony M9

   C. Sony M400          D. Imperial OEM MC7

65. If you want a machine which turns off automatically and weighs very little you should choose _____.

   A. Pearlcorder S 702     B. Sony M9

   C. Sony M400          D. Philips 585

66. Which of the following allows you to record longest but costs you least?

   A. Philips 585          B. Imperial OEM MC7

   C. Sony M400          D. Sony M9

67. What disadvantage does only the Imperial OEM MC7 have?

   A. No light shows when it is on.

   B. It requires a special cassette.

   C. It picks up background noise.

   D. The record button makes a noise.

D

   The US Department of Labor statistics show that there is an oversupply of college trained workers and that this oversupply is increasing. Already there have been more than enough, teachers, engineers, physicists, aerospace experts, and other specialists. Yet colleges and graduate schools continue every year to turn out highly trained people to compete for jobs that aren’t there. The result is that graduates cannot enter the professions for which they were trained and must take temporary jobs which do not require a college degree.

   On the other hand, there is a great need for skilled workers of all sports: carpenters, electricians, mechanics, plumbers, TV repairmen. These people have more work than they can deal with, and their annual incomes are often higher than those of college graduates. The old gap that white-collar workers make a better living than blue collar workers no longer holds true. The law of supply and demand now favors the skilled workmen.

   The reason for this situation is the traditional myth that College degree is a passport to a prosperous future. A large part of American society matches success in life equally with a college degree. Parents begin indoctrinating(灌输) their children with this myth before they are out of grade school. High school teachers play their part by acting as if high school education were a preparation for college rather than for life. Under this pressure the kids fall in line. Whether they want to go to college or not doesn’t matter. Everybody should go to college, so of course they must go. And every year college enrollments(入学) go up and up, and more and more graduates are overeducated for the kinds of jobs available to them.

   One result of this emphasis on a college education is that many people go to college who do not belong there. Of the sixty percent of high school graduates who enter college, half of them do not graduate with their class. Many of them drop out within the first year. Some struggle on for two or three years and then give up.

68. It’s implied but not stated in the passage that _______.

   A. many other countries are facing the some problem

   B. white-collar workers in the US used to make more money than blue-collar workers

   C. fewer students will prefer to go to college in the future

   D. the law of supply and demand has a strong effect on American higher education

69. Which of the following is NOT a reason why college enrollments go up every year?

   A. Many believe the only way to success is a college education.

   B. Many parents want their children ? to go to college.

   C. High school teachers urge their students to go to college.

   D. Every young man and woman wants to go to college.

70. By saying that “many people go to college who do not belong there”, the author means that ______.

   A. many people unfit for college education go to college

   B. many people without enough money go to college

   C. many people going to college drop out within the first year

   D. many people going to college have their hopes destroyed

71. We can infer from the passage that the author believe that ______.

   A. every young man and woman should go to college

   B. college education is a bad thing

   C. people with a college education should receive higher pay

   D. fewer people should go to college while more should be trained for skilled jobs

E

   Anxiety is the appropriate emotion when the immediate personal terror ? of a volcano, an arrow, a stab(刺伤) in the back and other disasters ? is directed against one’s self-disappears.

   The kind of world that produces anxiety is actually a world of relative safety, a world in which no one feels that he himself is facing sudden death. The anxiety exists as an uneasy state of mind, in which one has a feeling that something unspecified(不具体的) an indeterminable may go wrong. If the world seems to be going well, this produces anxiety―for good times may end. If the world is going badly―it may get worse. Anxiety tends to be without focus; the anxious person doesn’t know whether to blame himself or other people. He isn’t sure whether it is the change in climate or the atom bomb that is to blame for this unclear sense of unease.

   It is clear that we have developed a society which depends on having the right amount of anxiety to make it work. While we agree that too much anxiety is harmful to mental health, we have come to rely on anxiety to push us into seeing a doctor about a symptom (症状) which may indicate cancer, into checking up on that old life-insurance policy which may have out-of-date provisions in it, into having a conference with Billy’s teacher even though his report card looks all right.

   People who are anxious enough keep their care insurance up, have the brakes checked, and don’t take a second drink when they have to drive. People who are too anxious either refuse to go into cars at all or drive so tensely that they help cause accidents. People who aren’t anxious enough take chance after chance, which increases the terrible accidents of the roads.

72. In the world that produces anxiety, _______.

   A. people have sudden uneasiness

   B. everything goes well

   C. people are clear about their life

   D. danger is almost everywhere

73. The author holds that ______.

   A. anxiety is a good thing

   B. anxiety is a symptom of mental illness

   C. some anxiety can lead to changes for the better

   D. no anxiety is bad for society

74. Accidents of the road tend to be caused by _______.

A. all those who are too anxious

B. all those who have anxiety

C. those who have no anxiety

D. those who are not anxious enough

75. The best title for the passage would be _______.

A. Anxiety

B. The Right Amount of Anxiety

C. Anxiety vs Safety

D. Different Attitudes to Anxiety

 

V. 短文改错

Deal Paul,

How is everything? I’m writing to tell you about                

the race be held next Tuesday. You are one                         76. _____

of the ten runner in your class in the race, and you                   77. _____

need to be at school gate by 1:30 pm that day. The                   78. _____

race began at 1:40. All racers will start from the gate. Then            79. _____

turn right and run along Zhongshan Road till you see the              80. _____

traffic lights there you’ll turn right again and keep running             81. _____

along Guang’an Street till you will come to the Post Office.            82. _____

There turn right, go on to the bank of the river, crossing the bridge      83. _____

and take a left turn. Finally, they are to reach the finish line.           84. _____

By the way, if you want much information, please let me know.         85. _____

VI. 书面表达

   高三学生面临着沉重的学习压力,很多学生利用课间十分钟的休息时间学习,实际上没有什么效果。假如你是新华中学高三年级的学生李越,就此现象给中学生英语报写封信,发表自己的看法。信的内容须包括以下要点:

   1.十分钟的课间休息很有必要(说明理由);

   2.你是怎样利用这十分钟的。

   注意:1、词数100-200; 2、信的开头已经给出(不计入总数)。

Dear editor,

   I’m a Senior 3 student from Xinhua Middle School. ________________________

_______________________________________________________________________________________________________________________________________________________________________________________________________________

 

 

 

 

 

 

Answers:

BDCAA   BCCAA   ABBAC  CDBAA

21-25 BBACD  26-30 CDADA  31-35 BDCDB

36-40 ADADC  41-45 BACBA  46-50 CDBAD  51-55 BCADC

56-59 BDBC    60-63 CBDA   64-67 ACDB   68-71 BDAD   72-75 BCDA

76. be 前加 to  

77. runner--- runners

78. at 后加 the

79. began --- begins

80. 对

81.there --- where

82. 去掉 will

83. crossing --- cross

84. they --- you

85. much --- more

 

Dear editor,

   I’m a Senior 3 student from Xinhua Middle School. As is known to all, senior 3 students are suffering heavy pressure of study. As a result, many students are trying to spare every minute to study, even during the ten-minute break between classes.

   In my opinion, taking the ten-minute break between classes is definitely necessary, which makes us relaxed both physically and mentally. The ten-minute break is menat for us to relax and prepare for the next class. Only by doing so can we have more energy to study effectively in class.

   My ten-minute break is always pleasing as well as relaxing. Sometimes I do some simple exercises. Sometimes I have a free chat with my classmates or just take walk outside. Therefore, I always feel energetic and listen attentively in class.

 

 

 

试题详情

黑龙江省哈尔滨市第六中学2009届高三第一次模拟考试

理科综合试卷

本试卷分第I卷(选择题)和第II卷(非选择题)两部分。满分300分。考试时间150分钟

第I卷 (选择题  共126分)

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黑龙江省哈尔滨市第六中学2009届高三第一次模拟考试

文科综合试题

试卷分为第Ⅰ卷(选择题)和第Ⅱ卷(综合题)两部分,满分300分,考试时间150分钟。

注意事项∶

1.答第Ⅰ卷前,考生务必将自己的姓名、准考证号、考试科目涂写在答题卡上。考试结束,将试题卷和答题卡一并交回。

2.每小题选出答案后,用铅笔把答题卡上对应题目的答案标号涂黑,如需改动,用橡皮擦干净后,再选涂其他答案,不能答在试题卷上。

第Ⅰ卷(选择题,共140分)

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黑龙江省哈尔滨市第六中学2009届高三第一次模拟考试

数学理科试卷

本试卷分第卷(选择题)和第 卷(非选择题)两部分,满分150分,考试用时120分钟;

卷(选择题  满分60分)

试题详情

黑龙江省哈尔滨市第六中学2009届高三第一次模拟考试

数学文科试卷

本试卷分第卷(选择题)和第 卷(非选择题)两部分,满分150分,考试用时120分钟;

卷(选择题  满分60分)

试题详情

专题四 电学实验

电学实验是高考实验考查的重点、热点内容。试题注重联系实验操作的考查,如测量仪器的读数问题、实验线路的连线问题、电表和其他用电器的选择问题都是实验操作的仿真模拟,需要考生具备良好的动手实践经验。试题还注重实验数据的处理分析,如根据实验数据画出图线,根据图线分析得出结论。“设计和完成实验的能力”在理科综合《考试说明》中指出的五个考试目标之一。是近几年高考物理实验题的命题趋向。

完整的设计一个实验,要经历多个环节,在实际考查中,一般不会考查全部环节,而是只考查其中的几个环节,有的题目给出条件和实验器材,要求阐述实验原理;有的给出实验电路图,要求领会实验原理,确定需测物理量及计算公式;有的则要求考生根据操作步骤及测定的物理量判断出实验原理……虽然考查方式不尽相同,但目前高考中几乎所有的设计型实验题都有一个共同点,都以不同方式或多或少的对实验原理作一定的提示,在给出实验器材的前提下进行考查。

由于考查环节和要求的不同,题型也不尽相同,但较多的是选择、填空、作图题。

在复习过程中,应对所学电学实验逐个理解实验原理、实验方法,比较不同实验的异同(如电路图、滑动变阻器和电表的连接)。不断充实自己的经验和方法,逐步达到能灵活运用已学知识解答新的问题。对于设计型实验题目要明确实验设计的关键在于实验原理的设计,它是进行实验的依据和起点,它决定了应选用(或还需)哪些实验器材,应测量哪些物理量,如何编排实验步骤。而实验原理的设计又往往依赖于所提供的实验器材(条件)和实验要求,它们相辅相成,互为条件。

(一)电学实验中所用到的基本知识

在近年的电学实验中,电阻的测量(包括变形如电表内阻的测量)、测电源的电动势与内电阻是考查频率较高的实验。它们所用到的原理公式为:。由此可见,对于电路中电压U及电流I的测量是实验的关键所在,但这两个量的直接测量和间接测量的方法却多种多样,在此往往也是高考试题的着力点之处。因此复习中应熟练掌握基本实验知识及方法,做到以不变应万变。

1.电路设计原则:正确地选择仪器和设计电路的问题,有一定的灵活性,解决时应掌握和遵循一些基本的原则,即“安全性”、“方便性”、“精确性”原则,兼顾“误差小”、“仪器少”、“耗电少”等各方面因素综合考虑,灵活运用。

⑴正确性:实验原理所依据的原理应当符合物理学的基本原理。

⑵安全性:实验方案的实施要安全可靠,实施过程中不应对仪器及人身造成危害。要注意到各种电表均有量程、电阻均有最大允许电流和最大功率,电源也有最大允许电流,不能烧坏仪器。

⑶方便性:实验应当便于操作,便于读数,便于进行数据处理。

⑷精确性:在实验方案、仪器、仪器量程的选择上,应使实验误差尽可能的小。

2.电学实验仪器的选择:

⑴根据不使电表受损和尽量减少误差的原则选择电表。首先保证流过电流表的电流和加在电压表上的电压均不超过使用量程,然后合理选择量程,务必使指针有较大偏转(一般要大于满偏度的1/3),以减少测读误差。

⑵根据电路中可能出现的电流或电压范围选择滑动变阻器,注意流过滑动变阻器的电流不超过它的额定值,对大阻值的变阻器,如果是滑动头稍有移动,使电流、电压有很大变化的,不宜采用。

⑶应根据实验的基本要求来选择仪器,对于这种情况,只有熟悉实验原理,才能作出恰当的选择。总之,最优选择的原则是:方法误差尽可能小;间接测定值尽可能有较多的有效数字位数,直接测定值的测量使误差尽可能小,且不超过仪表的量程;实现较大范围的灵敏调节;在大功率装置(电路)中尽可能节省能量;在小功率电路里,在不超过用电器额定值的前提下,适当提高电流、电压值,以提高测试的准确度。

3.测量电路的选择

⑴电流表的内、外接问题:(甲)所示电路为电流表外接电路(简称外接法);(乙)所示电路为电流表内接电路(简称内接法)。两种接法的选择可按下列方法进行:

方法一:设电流表、电压表内阻分别为,被测电阻为,则

<时,电压表分流作用小,应选用外接法

>时,电流表分压作用小,应选用内接法

=时,电流表分压作用和电压表分流作用相差不大,两种方法均可。

方法二:在均不知的情况下,可采用试触法。如图所示,分别将a端与b、c接触,如果前后两次电流表示数比电压表示数变化明显,说明电压表分流作用大,应采用内接法;如果前后两次电压表示数比电流表示数变化明显,说明电流表分压作用大,应采用外接法。

 

 

 

 

⑵滑动变阻器的分压、限流接法:

为了改变测量电路(待测电阻)两端的电压(或通过测量电路的电流),常使滑动变阻器与电源连接作为控制电路,滑动变阻器在电路中主要有两种连接方式:如图(甲)为滑动变阻器的限流式接法,为待测电阻。它的接线方式是电源、滑动变阻器与待测电阻三者串联。对待测电阻供电电压的最大调节范围是:(是待测电阻,R是滑动变阻器的总电阻,不计电源内阻)。如图(乙)是滑动变阻器的分压式接法。接线方式是电源与滑动变阻器组成闭合电路,而被测电路与滑动变阻器的一部分电阻并联,该接法对待测电阻供电电压的调节范围是:(不计电源内阻时)。

选取接法的原则:

①要求负载上电压或电流变化范围大,且从零开始连续可调,须用分压式接法。

②负载电阻Rx远大于滑动变阻器总电阻R时,须用分压式接法,此时若采用限流式接法对电路基本起不到调节作用。

③采用限流电路时,电路中的最小电流(电压)仍超过电流表的量程或超过用电器的额定电流(电压)时,应采用变阻器的分压式接法。

④负载电阻的阻值Rx小于滑动变阻器的总电阻R或相差不大,并且电压表、电流表示数变化不要求从零开始起调,可用限流式接法。

⑤两种电路均可使用时应优先用限流式接法,因为限流电路结构简单,总功率较小。

滑动变阻器的粗调和微调作用:

①在限流电路中,全电阻较大的变阻器起粗调作用,全电阻较小的变阻器起微调作用。

②在分压电路中,全电阻较小的变阻器起粗调作用,全电阻较大的变阻器起微调作用。

4.实物图的连接:实物图连线应掌握基本方法和注意事项。

⑴注意事项:

①连接电表应注意量程选用正确,正、负接线柱不要接错。

②各导线都应接在接线柱上,不应在导线中间出现分叉。

③对于滑动变阻器的连接,要搞清楚接入电路的是哪一部分电阻,在接线时要特别注意不能将线接到滑动触头上。

⑵基本方法:

①画出实验电路图。

②分析各元件连接方式,明确电流表与电压表的量程。

③画线连接各元件。(用铅笔画线,以便改错)连线方式应是单线连接,连线顺序应先画串联电路,再画并联电路。

    一般先从电源正极开始,到电键,再到滑动变阻器等。按顺序以单线连接方式将干路中要串联的元件依次串联起来;然后连接支路将要并联的元件再并联到电路中去。连接完毕,应进行检查,检查电路也应按照连线的方法和顺序。

(二)定值电阻的测量方法

1.欧姆表测量:最直接测电阻的仪表。但是一般用欧姆表测量只能进行粗测,为下一步的测量提供一个参考依据。用欧姆表可以测量白炽灯泡的冷电阻。

2.替代法:替代法的测量思路是等效的思想,可以是利用电流等效、也可以是利用电压等效。替代法测量电阻精度高,不需要计算,方法简单,但必须有可调的标准电阻(一般给定的仪器中要有电阻箱)。

【例题】在某校开展的科技活动中,为了要测出一个未知电阻的阻值Rx,现有如下器材:读数不准的电流表A、定值电阻R0、电阻箱R1、滑动变阻器R2、单刀单掷开关S1、单刀双掷开关S2、电源和导线。

⑴画出实验电路图,并在图上标出你所选用器材的代码。

⑵写出主要的实验操作步骤。

【解析】⑴实验电路如右图所示。

⑵①将S2与Rx相接,记下电流表指针所指位置。②将S2与R1相接,保持R2不变,调节R1的阻值,使电流表的指针指在原位置上,记下R1的值,则Rx=R1

3.伏安法:伏安法的测量依据是欧姆定律(包括部分电路欧姆定律和全电路欧姆定律),需要的基本测量仪器是电压表和电流表,当只有一个电表(或给定的电表不能满足要求时),可以用标准电阻(电阻箱或一个定值电阻)代替;当电表的内阻已知时,根据欧姆定律I=U/R电压表同时可以当电流表使用,同样电流表也可以当电压表用。

4.伏安法拓展:某些问题中,因实验器材不具备(缺电流表或电压表),或因实验条件限制,或因实验精度不允许而不能用“伏安法”。这时我们就得依据问题的具体条件和要求重新选择实验原理,用“伏安法”的替代形式――“比较法”来设计实验方案。

⑴利用已知内阻的电压表:利用“伏伏”法测定值电阻的阻值

【例题】用以下器材测量一待测电阻Rx的阻值(900~1000Ω):

电源E,具有一定内阻,电动势约为9.0V;

电压表V1,量程为1.5V,内阻r1=750Ω;

电压表V2,量程为5V,内阻r2=2500Ω;

滑动变阻器R,最大阻值约为100Ω;

单刀单掷开关K,导线若干。

测量中要求电压表的读数不小于其量程的1/3,试画出测量电阻Rx的一种实验电路原理图。

【解析】如图所示

 

 

 

 

 

 

 

⑵利用已知内阻的电流表:利用“安安”法测定值电阻的阻值

【例题】用以下器材测量一待测电阻的阻值。器材(代号)与规格如下:

电流表A1(量程250mA,内阻r1为5Ω);标准电流表A2(量程300mA,内阻r2约为5Ω);

待测电阻R1(阻值约为100Ω);滑动变阻器R2(最大阻值10Ω);

电源E(电动势约为10V,内阻r 约为1Ω);单刀单掷开关S,导线若干。

⑴要求方法简捷,并能测多组数据,画出实验电路原理图,并标明每个器材的代号.

⑵需要直接测量的物理量是_______,用测的量表示待测电阻R1的计算公式是R1=________。

 

【解析】⑴实验电路图如图所示。

 

 

 

 

⑵两电流表A1、 A2的读数为I1、I2和电流表A1的内阻为r1,待测电阻R1的阻值的计算公式是:

 

 

⑶电压表、电流表混合用

【例题】有一电阻Rx,其阻值在100~200Ω之间,额定功率为0.25W。要用伏安法较准确地测量它的阻值,实验器材有:

安培表A1,量程为50mA,RA1=100Ω

安培表A2,量程为1A,RA2=20Ω

电压表V1,量程为5V,RV1=10kΩ

电压表V2,量程为15V, RV2=30kΩ 

变阻器R1,变阻范围0~20Ω ,2A

变阻器R2,变阻范围0~1000Ω,1A

9V电源,电键,导线。

⑴实验中应选用的电流表、电压表、变阻器分别是:                                。   

⑵画出所用实验电路图。

【解析】⑴允许通过电阻中电流可能的最大值由:得,。因为电阻可能为200Ω,所以通过被测电阻的电流的最大值可能是35mA,应用电流表的示数来控制通过电阻的电流,因此,电流表应选A1。又因为,所以 。因为电阻可能为100Ω,所以允许加在电阻两端的电压的最大值可能是5V,应用电压表的示数来控制加在电阻两端的电压,因此电压表应选V1。因为R1< R2,且2A>35mA, 所以应选变阻器R1。因为R1<Rx 所以滑动变阻器连接方式应选用分压电路。因为<,  所以应选用外接电路。

⑵实验所用电路如图所示

 

 

 

 

【变式题】(2006年广东)某同学设计了一个如图甲所示的实验电路,用以测定电源电动势和内阻,使用的实验器材为:待测干电池组(电动势约3 V)、电流表(量程0.6 A,内阻小于1 Ω)、电阻箱(0~99.99 Ω)、滑动变阻器(0~10 Ω)、单刀双掷开关、单刀单掷开关各一个及导线若干。考虑到干电池的内阻较小,电流表的内阻不能忽略。

⑴该同学按图甲连线,通过控制开关状态,测得电流表内阻约为0.20 Ω。试分析该测量产生误差的原因是_________________________________________。

⑵简要写出利用图甲所示电路测量电源电动势和内阻的实验步骤:

①_____________________________________________________________________       

②______________________________________________________________________      

⑶图乙是由实验数据绘出的图象,由此求出待测干电池组的电动势E=______V、内阻

r=______  Ω。(计算结果保留三位有效数字)

 

 

 

 

 

 

 

 

 

 

 

 

 

 

【解析】由测定电源电动势和内阻实验的原理知,此种接法出现误差的原因是电流表的分压作用。而图线的斜率表示电源电动势的倒数,据此得出电动势E=2.81V, 内 阻

 r=2.33Ω。若不能正确理解图象的物理意义,则无法得出正确的答案。因此对于实验中处理数据的图像的意义,一定要分析清楚。

【答案】⑴并联电阻箱后线路总阻值减小,从而造成总电流增大                          

⑵ ①调节电阻箱R,断开开关K,将开关 S接D,记录电阻箱的阻值和电流表示数;

②断开开关D,再次调节电阻箱R,将开关S接D,记录电阻箱的阻值和电流表示数

⑶ 2.81、2.33

(三)电表内阻的测量方法

1.互测法:

⑴电流表、电压表各一只,可以测量它们的内阻:

 

 

 

⑵两只同种电表,若知道一只的内阻,就可以测另一只的内阻:

 

 

 

⑶两只同种电表内阻都未知,则需要一只电阻箱才能测定电表的内阻:

 

 

 

 

2.替代法:

 

 

 

 

3.半偏法:

 

 

 

          

 

4.闭合电路欧姆定律计算法:(不计电源内阻)

 

【例题1】(2000年全国)从下表中选出适当的实验器材,设计一电路来测量电流表A1的内阻r1,要求方法简捷,有尽可能高的测量精度,并能测得多组数据。

⑴在虚线方框中画出电路图,标明所用器材的代号。

器材(代号)

规    格

电流表(A1

量程10mA,内阻r1待测(约40Ω)

电流表(A2

量程500μA,内阻r2=750Ω

电压表(V)

量程10V,内阻r3=10Ω

电阻(R1

阻值约100Ω,作保护电阻用

滑动变阻器(R)

总阻值约50Ω

电池(E)

电动势1.5V,内阻很小

导线若干,电键K

 

t16.bmp (44946 bytes)⑵若选测量数据中的一组来计算r1,则所用的表达式为r1=____________,式中各符号的意义是____________。

【解析】⑴如图所示。  

,I1表示通过电流表A1的电流,I2表示通过电流表A2的电流,

r2表示电流表A2的内阻。

【备考提示】在很多情况下,电压表和电流表(已知内阻)的功用可以互换。有时利用一块电表配合定值电阻也可以完成功能的互换。实际上就是部分电路欧姆定律的变形运用。在处理时,一定要明确原理,灵活运用。

【例题2】(2006年全国Ⅰ、Ⅲ)现要测量某一电压表   的内阻。给定的器材有:待测电压表   (量程2V,内阻约4kΩ);电流表   (量程1.2mA,内阻约500Ω);直流电源E(电动势约2.4V,内阻不计);固定电阻3个:R1=4000Ω,R2=10000Ω,R3=15000Ω;电键S及导线若干。要求测量时两电表指针偏转均超过其量程的一半。

⑴试从3个固定电阻中选用1个,与其它器材一起组成测量电路,并在虚线框内画出测量电路的原理图。(要求电路中各器材用题中给定的符号标出。)

⑵电路接通后,若电压表读数为U,电流表读数为I,则电压表内阻RV =_________。

 

【解析】⑴实验电路如图所示,若选用电阻R1,则并联电阻=2000Ω,电压表读数

U=?R×2000=1.92>1V,电流表读数I==0.00096A=0.96mA>0.6mA,R1符合要求,同理可得R2、R3不符合要求,故选R1

⑵电路接通后,通过R1的电流I1,则通过电压表的电流为I2=I-I1=I-,所以电压表的内阻RV

【备考提示】本题涉及实验器材选取和电路设计等,对考生的分析综合能力提出了较高要求,解答此类试题必须根据测量要求和所提供的器材,由仪表的选择原则和基本规律为分析的入手点。

【变式题】

1.(2006年全国Ⅱ)现要测定一个额定电压4V、额定功率1.6W的小灯泡(图中用×表示)的伏安特性曲线。要求所测电压范围为0.1V~4V。

现有器材:直流电源E(电动势4.5V,内阻不计),电压表    (量程4.5V,内阻约为4×104Ω),电流表   (量程250mA,内阻约为2Ω),电流表   (量程500mA,内阻约为1Ω),滑动变阻器R(最大阻值约为30Ω),电键S,导线若干。

如果既要满足测量要求,又要测量误差较小,应该选用的电流表是          ,下面两个电路应该选用的是               

【解析】在测量小灯泡的伏安曲线时,由于题目要求电压范围为0.1V~4V,因此滑动变阻器采用分压式接法。根据估算通过小灯泡的额定电流为I=0.4A,因此电流表应该选用    。在伏安法测量过程中,由于

临界电阻大于小灯泡电阻,因此应该选择电流表外接法即选择甲电路进行测量。

 

 

2.(2006年北京)某同学用如图所示电路,测绘标有“3.8 V,0.3 V”的小灯泡的灯丝电阻R随电压U变化的图象。

①除了导线和开关外,有以下一些器材可供选择:
电流表:A 1(量程100 mA,内阻约2Ω)
        A2 (量程0.6 A,内阻约0.3Ω)
电压表:V1(量程5 V,内阻约5Ω)
        V2(量程15 V,内阻约15Ω)
电源:E1(电动势为1.5 V,内阻为0.2Ω)
      E2(电动势为4 V,内阻约为0.04Ω)
为了调节方便,测量准确,实验中应选用电流表___________,电压表______________,滑动变阻器________________,电源___________________。(填器材的符号)
②根据实验数据,计算并描绘出R-U的图象如图所示。由图象可知,此灯泡在不工作时,灯丝电阻为___________;当所加电压为3.00 V时,灯丝电阻为____________,灯泡实际消耗的电功率为___________W。
         

③根据R-U图象,可确定小灯泡耗电功率P与外加电压U的关系,符合该关系的示意图是下列图中的__________。

 

 

 

 

【解析】①对器材的选用应以安全、实用为原则。小灯泡的额定电压和额定电流分别为3.8V和0.3A,故电压表应选V1,电流表A2;由于是分压接法,故滑动变阻器应选R1,便于调节,电源应选E2。②由图象可看出:U=0时,小灯泡不工作,对应电阻为1.5Ω,当U=3.0V时,对应的电阻为11.5Ω。此时,灯泡实际消耗的功率P==0.78W。③由R-U图线可看出,随U的增大,电阻的变化越来越小,而P=,随U的变化,功率P的变化将更加明显,故选A。

(四)一类借助图像法处理的上海实验试题

近几年的上海高考中,经常出现一类需要借助图像关系处理的实验题,该种题目处理技巧性强,并且要求能够准确理解图像的物理意义,该类问题对于山东的命题不无导向作用,备考时也应引起足够的重视。

【例题1】(2004年上海)两个额定电压为220V的白炽灯L1和L2的U ? I 特性曲线如图所示。L2的额定功率约为     W;现将L1和L2串联后接在220V的电源上,电源内阻忽略不计。此时L2的实际功率约为      W。

【解析】99,17.5

【备考提示】本题借助于图像信息,考查了用电器功率的计算以及用电器的串并联关系,解答时充分挖掘图像信息是解答的关键所在。同时要注意将L1和L2串联后接在220V的电源上时,在图像中的表达信息为:L1和L2在某一相同电流值下,电压和为220V,很多学生不能找出该隐含条件,从而造成第二问感到无从下手。

【例题2】(2004年上海)小灯泡灯丝的电阻会随温度的升高而变大。某同学为研究这一现象,用实验得到如下数据(I和U分别表示小灯泡上的电流和电压):

I ( A )

0.12

0.21

0.29

0.34

0.38

0.42

0.45

0.47

0.49

0.50

U (V )

0.20

0.40

0.60

0.80

1.00

1.20

1.40

1.60

1.80

2.00

⑴在左下框中画出实验电路图。 可用的器材有:电压表、电流表、滑线变阻器(变化范围0 ― 10 Ω)、电源、小灯泡、电键、导线若干。

⑵在右图中画出小灯泡的U ? I 曲线。

 

 

 

 

 

 

 

 

 

 

⑶如果将本题中的小灯泡接在电动势是1.5V,内阻是2.0 Ω的电池两端,小灯泡的实际功率是多少?(简要写出求解过程;若需作图,可直接画在第⑵小题的方格图中)

【解析】⑴分压器接法(如下图所示)。⑵如下图所示。⑶作出电源的U=E-Ir图线,该图线与小灯泡的U ? I 曲线相交于一点,由此可得小灯泡工作电流为0.35 A,工作电压为0.80 V,实际功率为0.28 W。

 

 

 

 

 

 

 

 

 

【备考提示】《研究小灯泡的伏安特性曲线》是高考考纲中规定的学生实验,对⑴⑵两问学生在实验复习中已基本掌握,而第⑶问则对实验数据的处理进行了拓展、延伸,对小灯泡的实际功率无计算公式,只能在小灯泡的伏安特性曲线上画出电池的U―I图线,然后找出两曲线的交点,从而确定此时灯泡的工作状态,得到实际工作功率。这考查了学生对小灯泡的伏安特性曲线的理解和实验数据处理的能力。同时也要深入理解图线交点与电路工作状态的对应关系。

【变式题】

1.(2003年上海)如图所示,图1为某一热敏电阻(电阻值随温度的改变而改变,且对温度很敏感)的I-U关系曲线图。

⑴为了通过测量得到图1所示I-U关系的完整曲线,在图2和图3两个电路中应选择的是图_____;简要说明理由                                  。(设滑线变阻器两端电压恒为9V,滑线变阻器的阻值为0~100Ω)。

文本框: 热敏电阻
 

 

 

 

 

 

 

⑵在图4电路中,电源电压恒为9V,电流表读数为70mA,定值电阻R1=250Ω。由热敏电阻的I-U关系曲线可知,热敏电阻两端的电压为________V;电阻R2的阻值为_____   _ Ω。

⑶举出一个可以应用热敏电阻的例子:_________________________                  

【解析】⑴2;图2电路电压可从0V调到所需电压,调节范围较大。(或图3电路不能测得0V附近的数据) ⑵5.2;111.8(111.6-112.0均给分) ⑶热敏温度计(提出其他实例,只要合理均给分)

2.(2005年上海)右图中图线①表示某电池组的输出电压――电流关系,图线②表示其输出功率――电流关系。该电池组的内阻为_____Ω。当电池组的输出功率为120W时,电池组的输出电压是_____V。

【解析】5,30

3.(2006年上海)表格中所列数据是测量小灯泡U―I关系的实验数据:

U/(V)

0.0

0.2

0.5

1.0

1.5

2.0

2.5

3.0

I/(A)

0.000

0.050

0.100

0.150

0.180

0.195

0.205

0.215

⑴分析上表内实验数据可知,应选用的实验电路图是图    (填“甲”或“乙”)

 

 

 

 

⑵在方格纸内画出小灯泡的U―I曲线。分析曲线可知小灯泡的电阻随I变大而         (填“变大”、“变小”或“不变”)

⑶如图丙所示,用一个定值电阻R和两个上述小灯泡组成串并联电路,连接到内阻不计、电动势为3V的电源上。已知流过电阻R的电流是流过灯泡b电流的两倍,则流过灯泡b的电流约为       A。

【解析】⑴由小灯泡 U―I关系的实验数据可得,电路中灯泡两端的电压可调为0,只有甲电路具有此功能,而乙图的电路不具此功能。故确定实验电路为甲。

⑵U―I曲线如右图所示,由所做出的U―I曲线知,曲线上各点与原点连线的斜率越来越大,说明灯泡的电阻越来越大。

⑶设b中的电流为I,依题意知a中的电流为3I,由,可估计。从曲线上得此时

 

试题详情

四川省乐山市高中2009届第二次调查研究考试

文科综合能力测试

本试卷分为第I卷(选择题)和第Ⅱ卷(综合题)两部分。第1卷l―6页,第Ⅱ卷7―14页。共300分。

第I卷  (选择题140分)

注意事项:

1.答第Ⅰ卷前,考生务必将自己的姓名、考生号、考试科目涂在答题卡上。

2.每小题选出答案后,用铅笔把答题卡上对应题目的答案标号涂黑。如需改动,用像皮擦干净后,再选涂其他答案标号。不能答在试题卷上。

3.考试结束后,将题和答案一并交回。

试题详情

陕西省宝鸡市2009年高三教学质量检测(二)

理科综合能力试题

注意事项:

       1.本试题共300分。考试时间150分钟

       2.考生一律将答案涂写在答题卡相应的位置上,不能答在试卷上。

       3.考试结束,将本试卷和答题卡一并交回。

可能用到的相对原子质量:H 1  C 12  O 16  Na 23  Cu 64

 

试题详情

绝密★启用前                                                 试卷类型:A

2009年深圳市高三年级第二次调研考试

数学(理科)           2009.5

本试卷共6页,21小题,满分150分.考试用时120分钟.

注意事项:

1.答卷前,考生首先检查答题卡是否整洁无缺损,监考教师分发的考生信息条形码是否正确;之后务必用0.5毫米黑色字迹的签字笔在答题卡指定位置填写自己的学校、姓名和考生号,同时,将监考教师发放的条形码正向准确粘贴在答题卡的贴条形码区,请保持条形码整洁、不污损.

2.选择题每小题选出答案后,用2B铅笔把答题卡上对应题目的答案标号涂黑,如需改动,用橡皮擦干净后,再选涂其它答案,答案不能答在试卷上.不按要求填涂的,答案无效.

3.非选择题必须用0.5毫米黑色字迹的签字笔作答,答案必须写在答题卡各题目指定区域内相应位置上,请注意每题答题空间,预先合理安排;如需改动,先划掉原来的答案,然后再写上新的答案;不准使用铅笔和涂改液.不按以上要求作答的答案无效.

4.作答选做题时,请先用2B铅笔填涂选做题的题号对应的信息点,再做答.漏涂、错涂、多涂的答案无效.

5.考生必须保持答题卡的整洁,考试结束后,将答题卡交回.

参考公式:

锥体的体积公式高考资源网( www.ks5u.com),中国最大的高考网站,您身边的高考专家。, 其中高考资源网( www.ks5u.com),中国最大的高考网站,您身边的高考专家。是锥体的底面积, 高考资源网( www.ks5u.com),中国最大的高考网站,您身边的高考专家。是锥体的高.

试题详情

现在完成时专题讲座:

一、基本结构:have (has) + done

二、基本概念:

1.     过去发生的一个动作 或者存在的某个状态,对现在造成了影响或者结果;(这里的动词需要用结束性动词)

        

 He ______ (die).

          The war _______ (break) out.

2.     过去发生的一个动作或存在的某个状态,一直持续到现在,对现在造成了影响或者结果。(这里的动词需要用延续性动词)

          He ______ (be) a teacher for ten years.

          He _______ (be) a teacher since ten years ago.

          We _______ (work) at this school for 3 years.

试题详情