题目内容

It is bad to have food stuck between your teeth for long periods of time. This is because food attracts germs; germs produce acid, and acid hurts your teeth and gums. Flossing (使用牙线) helps to remove the food that gets stuck between your teeth. This explains why flossing helps to keep your mouth healthy, but some doctors say that flossing can also be good for your heart.

It may seem strange that something you do for your teeth can have any effect on your heart. Doctors have come up with a few ideas about how flossing works to keep your heart healthy. One idea is that the germs that hurt your teeth can leave the mouth and travel into your blood.Germs that get into the blood can then attack your heart. Another idea is based on the fact that when there are too many germs in your mouth, the body tries to fight against there germs. For some reason, the way the body fights these mouth germs may end up weakening the heart overtime.

Not every doctor agrees about these ideas. Some doctors think that the link between good flossing habits and good heart health is only a coincidence. The incidence (发生率) of two or more events is completely random, as they do not admit of any reliable cause and effect relationship between them. For example, every time I wash my car, it rains. This does not mean that when I wash my car, I somehow change the weather. This is only a coincidence. Similarly, some doctors think that people who have bad flossing habits just happen to also have heart problems, and people who have good flossing habits just happen to have healthy hearts.

The theory that flossing your teeth helps to keep your heart healthy might not be true. But every doctor agrees that flossing is a great way to keep your teeth healthy. So even if flossing does not help your heart, it is true to help your teeth. This is enough of a reason for everyone to floss their teeth every day.

1.From the passage, we know that ________.

A. food stuck between your teeth may hurt your teeth

B. all of the doctors agree that flossing is good for your heart

C. doctors’ judgment about flossing is based on medical research

D. not every doctor thinks flossing helps to keep your teeth healthy

2.The underlined sentence in Paragraph 3 is to ________.

A. provide an example

B. make a comparison

C. introduce a new topic

D. develop the previous statement

3.Which of the following best states the main idea of the last paragraph?

A. It is a fact that flossing can help your heart as well as your teeth.

B. There is no good reason to believe that flossing will help your heart.

C. Because doctors find flossing won’t help your heart, it is useless to floss.

D. Even if flossing is only good for your teeth, you should still do it every day.

4.Which is the best title for the passage?

A. Flossing by Coincidence

B. How to Keep Your Teeth Healthy

C. Flossing Habits and Healthy Hearts

D. Why Doctors Disagree About Flossing

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阅读下面短文,从短文后各题所给的四个选项(A、B、C、D)中,选出可以填入空白处的最佳选项。

A Person Who Has Influenced My Life

There is always a time in one’s life when a hero comes along. Someone who has inspired you can really help you learn what life is about.

I ____ it as if it was yesterday. I was fifteen years old that year. It was around eight o’clock one evening when my mother ____ a phone call from her brother-in-law, who told us my aunt was in hospital and that the doctor ____ them she would need an operation immediately. My family became very ____ about my aunt’s situation.

While my aunt was in the hospital with special ____, my cousin Mark, who is mentally disabled, spent time with my family. Mark was seventeen at the time, and had been born with severe mental disorders, which ____ a wide range of social and physical problems for him throughout everyday life. He never had any true friend ___ no one could relate to him. I must ____ that at the beginning I was filled with uncertainty as to how much of a ___ my cousin would bring on my family. Now looking back it saddens me to see the ___ I once showed.

Over the two weeks when Mark lived with my family, I probably ____ more about life and its meanings. Thinking back, I took ____ in daily life for granted, believing it would always be there. I never even thought about being able to do things like walking, brushing my teeth, or going to the bathroom on my own. Now I see how ____ I am to be able to do these things independently.

Mark was seventeen, but learned on a nine-year-old ____. Although his learning ability was slower than most, he could still learn. He explored ____ to do most of the things everyone else did. ____ he did pretty well and succeeded in almost everything he tried to do. He ____ his illness and showed an ambition to love life. To him, having a successful life means achieving goals on his own terms and at his own ____.

Mark is my hero, for his disability has forever ____ my viewpoint on life. It seems like a well-deserved life when you’re fifteen, and it is amazing how in a period of time your point of view can change so ____.

1.A. acceptB. rememberC. imagineD. discover

2.A. madeB. missedC. receivedD. used

3.A. promisedB. informedC. showedD. begged

4.A. curiousB. sureC. disappointedD. worried

5.A. careB. actionC. purposeD. interest

6.A. createdB. facedC. foundD. influenced

7.A. unlessB. althoughC. untilD. because

8.A. believeB. regretC. admitD. decide

9.A. puzzleB. failureC. burdenD. conflict

10.A. weaknessB. ignoranceC. reliefD. mercy

11.A. understoodB. dreamedC. questionedD. required

12.A. anythingB. somethingC. nothingD. everything

13.A. powerfulB. braveC. luckyD. successful

14.A. varietyB. levelC. jobD. balance

15.A. possibilitiesB. functionsC. achievementsD. difficulties

16.A. TypicallyB. OccasionallyC. AccidentallyD. Actually

17.A. challengedB. preventedC. treatedD. reported

18.A. businessB. costC. paceD. request

19.A. representedB. changedC. formedD. supported

20.A. easilyB. normallyC. properlyD. completely

A policeman was walking along the street. In the doorway of a shop, a man was standing in the ________ light, with an unlighted cigar in his mouth. The policeman ________ and then walked up to the man.

“I’m just waiting for a friend here,” the man said “It’s a(n) ________ made twenty years ago.” The man struck a match and ________ his cigar. The light ________ a pale face with a little white scar(疤) near his right eye. “Twenty years ago tonight, when I said goodbye to Jimmy Wells, my best friend to ________ for the West to make my fortune, we ________ we would meet here again exactly twenty years ________ that date and time.” “I hope your friend will come around soon.” said the policeman, ________.

Twenty minutes later, a(n) tall man hurried across the street. He went directly to the waiting man. “Is that you, Bob?” he asked. “Jimmy Wells?” ________ the man with excitement. “You have ________, Jimmy. I never thought you were so tall.”

When they both looked at each other ________, the man said suddenly “You’re not Jimmy Wells. Twenty years is a long time, ________ not long enough to change a man’s ________.” “It sometimes changes a good man into a ________ one,” said the tall man. “You are under ________ now. Well, here is a note from your friend.” His hand was steady when he began to read, but it ________ a little by the time he had finished. It reads: “Bob: I was at the appointed place ________. When you lighted your cigar I saw it was the face of the man ________ by Chicago police. ________ I couldn’t catch myself, so I went around and got a plain clothes man to do the job.”

1.A. darkB. brightC. dimD. colorful

2.A. slowed downB. picked outC. went onD. hurried up

3.A. mistakeB. timeC. tradeD. appointment

4.A. stoppedB. lightedC. burntD. dropped

5.A. formedB. appearedC. relievedD. showed

6.A. startB. workC. lookD. search

7.A. insistedB. preferredC. agreedD. suggested

8.A. forB. fromC. laterD. at

9.A. speeding upB. coming toC. pulling offD. moving away

10.A. criedB. smiledC. weptD. choked

11.A. grewB. achievedC. changedD. became

12.A. clearlyB. surprisinglyC. quicklyD. happily

13.A. butB. andC. orD. while

14.A. characterB. faceC. qualityD. size

15.A. successfulB. ordinaryC. tallD. bad

16.A. discussionB. controlC. arrestD. inspiration

17.A. trembledB. struggledC. escapedD. understood

18.A. in advanceB. on time

C. before longD. sooner or later

19.A. askedB. wantedC. describedD. caught

20.A. AnywhereB. ThoughC. HoweverD. Anyway

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