[题目]一船在灯塔C的正东方向8海里的A处.以20海里/时的速度沿北偏西30°方向行驶．(1)多长时间后.船距灯塔最近?(2)多长时间后.船到灯塔的正北方向?此时船距灯塔有多远?(其中:162-82≈13．92) 题目和参考答案——青夏教育精英家教网—

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【题目】一船在灯塔C的正东方向8海里的A处，以20海里/时的速度沿北偏西30°方向行驶．

（1）多长时间后，船距灯塔最近?

（2）多长时间后，船到灯塔的正北方向?此时船距灯塔有多远?(其中:162-82≈13．92)

【答案】(1)12分钟后，船距灯塔最近；（2）此时船距灯塔有13.9海里.

【解析】试题分析：（1）作出图象在直角三角形ACD中求得AD的长后除以速度即可求得时间；

（2）在直角三角形ACB中求得AB的长后除以速度即可求得时间，由勾股定理可求出此时船距灯塔的距离．

试题解析：(1)如图所示，由题意可知，当船航行到D点时，距灯塔最近，

此时，CD⊥AB．

因为∠BAC=90°-30°=60°，所以∠ACD=30°．

所以AD==4(海里)．

又因为4÷20=0．2(小时)=12(分钟)，

所以12分钟后，船距灯塔最近．

(2)当船到达灯塔的正北方向的B点时， BC⊥AC．

此时∠B=30°，

所以AB=2AC=2×8=16(海里)．

所以16÷20=0．8(小时)=48(分钟)．

所以BC2=AB2-AC2=162-82≈13． 92．

所以BC≈13．9(海里)．

即48分钟后，船到灯塔的正北方向，此时船距灯塔有13.9海里．

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提示:

(1)What do you like to do when you are free?

(2)Why are you interested in these things?

(3)What can you get from them?

要求:

(1)短文须包括所有要点，可适当发挥。

(2)短文中不得出现真实的人名、校名和地名。

(3)词数80个左右(开头已给出，不计入总词数)。

I have a lot of things to do in my free time.____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

【题目】 If you have a strong interest in a subject with several friends, you may want to start a club about it. By starting a club, you can share this common interest with them. You can also get some experience and this may help you a lot in the future. If you would like to do that, here are some good suggestions for you.

The most important requirement for starting a successful club is having a common interest with other students. With the common interest, they will be happy to join your club. This makes it easier to keep the club working well. So before starting a club, you must think about your common interest with other people.

You also need a teacher in your club. The teacher will start the first class and encourage students to join the club. You also need the teacher to be the advisor (顾问) for your club. When you are in trouble, you can ask the teacher for help.

When these things are ready, you need to choose your leader of the club. How do you choose the leader? You can discuss it with your club members. In the discussion, you also need to discuss the rules of the club with your partners so that each of the members can understand the rules better.

Do you want to be a top student and get good grades in your exams? You_can_follow_these_suggestions_and_start_your_club. Just do it.

1题完成句子；2～3题简略回答问题；4题找出并写下全文的主题句；5题将文中画线句子译成汉语。

【1】To start a successful club, the most important requirement is________________ with other students.

【2】Why do you need a teacher to be the advisor for your club?

________________________________________________________________________

【3】How do you choose the leader of your club?

________________________________________________________________________

【4】________________________________________________________________________

【5】________________________________________________________________________

【题目】 I have received many Christmas gifts over these years. The best gift I ever received was _______ by a stranger. I even never knew his name, and I only had contact with _______ for less than 60 seconds. His Christmas gift to me changed the way I think about people and Christmas.

I hate Black Friday sales. It's often a gathering of people who are there for many different reasons. Some are ______ one item for their loved one, or perhaps for themselves. Their intentions are completely unrelated to the happy time of a year, and can only be summed(总结) up with one word, “Cheap!”.

Several years ago, my mother asked me to meet her at the _______ market on Black Friday morning. She _______ to buy a bike for my brother. Many people were waiting for the selling. As the number of the bikes reduced, I knew I need to take one for my brother. I lifted up the box and _______ felt some mild resistance(阻力). A gentleman with Tattoos(纹身) made me feel _______.

I started to put the box back but he gently pushed it back into my _______ and directed it into my shopping cart. He looked at me, smiled and said, “Merry Christmas.” My mother and I went to the checkout, paid for the bike and went home.

On the way home I was thinking that this _______ was by far the best Christmas gift I had ever received. The kindness of a stranger ________ all preconceived(预想的) ideas. I will never forget it.

【1】A.givenB.gottenC.acceptedD.let

【2】A.youB.themC.himD.me

【3】A.leaving forB.asking forC.standing forD.caring for

【4】A.fullB.localC.specialD.dirty

【5】A.wantedB.allowedC.remindedD.solved

【6】A.silentlyB.quicklyC.politelyD.suddenly

【7】A.frightenedB.interestedC.relaxedD.bored

【8】A.legsB.armsC.eyesD.hands

【9】A.minuteB.momentC.troubleD.advice

【10】A.tookB.fixedC.madeD.changed

【题目】 There were two men who lived next to each other. One of them was a retired teacher and the other was a businessman. Both of them had planted many different plants in their gardens. The retired teacher seldom _____ his plants and didn't pay a lot of attention to them. But his neighbor was very _____ with his plants and watered them often.

The retired teacher's plants were small, but still looked okay, _____ the businessman's plants were much bigger and greener. One night, there came a storm with a heavy rain and strong wind. The next _____, both of the neighbors came out to check in their gardens. The businessman saw that his plants had come out from the _____ and were totally out of life. But the retired teacher's plants nicely _____ where they were.

The businessman was _____. He went to consult(咨询) the retired teacher. “We both grew the same plants and I _____ my plants better than you did. How could your plants still be okay?”

The retired teacher smiled and said, “Because you gave your plants too much_____. You made it too easy for them to ______. I gave my plants just a little bit of water, so they had to grow deeper to absorb(吸收) more water. That is why my plants survived.”

【1】A.wateredB.raisedC.checkedD.caught

【2】A.happyB.carefulC.familiarD.tired

【3】A.beforeB.sinceC.unlessD.while

【4】A.eveningB.afternoonC.morningD.noon

【5】A.houseB.floorC.skyD.earth

【6】A.heardB.tookC.stoodD.thought

【7】A.surprisedB.interestedC.excitedD.moved

【8】A.called forB.left forC.cared forD.looked for

【9】A.inventionB.attentionC.invitationD.action

【10】A.growB.plantC.stopD.die

【题目】用方框中所给单词的适当形式填空，使对话通顺、正确。每词仅用一次（每空一词）

Now more and more children are 【1】 very heavy. Maybe there are two main 【2】 .

Firstly, there are too many shops around schools. The shops sell unhealthy food, such as fried chicken and ice cream at low prices. So some children don’t like to eat at home. If there were fewer of these shops, then probably children would buy 【3】 junk food.

Secondly, children have bad 【4】 habits. They like fast food. Today we can see McDonald’s and KFC everywhere. Many children are crazy about fast food. In fact, 【5】 of the fast food is unhealthy because it has too much salt and sugar.