题目内容

— When did you go to bed last night?

— ____________ I finished my homework.

A. Until B. Not until C. When D. While

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Is it time for the students to do morning _____________?

A. to exercise B. exercises C. exercising D. exercise

— I’ll go on a trip with my friends next Sunday.

—_______.

A. Have a good time B. Good luck

C. Nice to meet you D. Yes, please

On June 26, 2000, two scientists, called Francis Collins and Craig Venter, told the world that they could now read the whole “map” of the human body: DNA．DNA is something that everybody has, and it tells the body what to do．DNA is the reason that we look like our mother and father, because we get some of their DNA to make our own．

People have been trying to understand the human body for a long time．In 1860, Gregor Mendel discovered a special reason why we look the same as other people in our family．It is because of small things named “genes” in our body．In 1953, James Watson and Francis Crick made another discovery and found out that those small parts are real messages written in the DNA with a special language．

In 1961, Marshall Nirenberg and Johann Mattaei found a message in DNA showing how DNA tells the cell (细胞) to build its parts．Scientists have now found all the words in the DNA map, but we still do not understand what they all do．By understanding what just one “word” means, we can help save more people from several illnesses．

Most people hope that this will help make better medicine and help sick people．Other people worry that when people begin to know more words and find out lots of other information, we might use it in a wrong way, just to make people more attractive, or stop sick people from getting jobs．Man will have to meet a lot of trouble if DNA technology (技术) isn’t limited in use．

1.When did we first know why we look like other people in our family?

A. In 1860． B. In 1953． C. In 1961． D. In 2000．

2.What does the underlined word “genes” mean in the passage?

A. The “map” of DNA． B. A special language．

C. Small parts of DNA． D. Several illnesses．

3.What did the two scientists first discover in 1961?

A. The “map” of DNA． B. A new illness．

C. The language of DNA． D. A message of DNA．

4.What can we do if we understand some “words” of the language inside the body?

A. Make people get new jobs． B. Make medicine for new illnesses．

C. Make maps of human． D. Make people less attractive．

5.What do people think about DNA technology?

A. It can cause good or bad results． B. It can cause good results．

C. It can cause good results but won’t work． D. It can cause only bad results．

Our teachers often tell us we can’t be _________ because no mistake is too small for us.

A. very careful B. careful C. so careful D. too careful

—Why are you looking __________ in class all day?

—Because I can’t finish my homework until eleven every night.

A. awake B. asleep C. sleeping D. sleepy

Can trees talk? Yes-but not in words. Scientists have reasons to believe that trees do communicate with each other. Not long ago, researchers learned some surprising things. First a willow tree(柳树) attacked in the woods by caterpillars (毛毛虫) changed the chemistry of its leaves and made them taste so terrible that the caterpillars got tired of the leaves and stopped eating them. The even more astonishing, the tree sent out a special vapor-a signal causing its neighbors to change the chemistry of their own leaves and make them less tasty.

Communication, of course, doesn’t need to be always in words. We can talk to each other by smiling, raising our shoulders and moving our hands. We know that birds and animals use a whole vocabulary of songs, sounds, and movements. Bees dance their signals, flying in certain patterns that tell other bees where to find nectar(花蜜) for honey. So why shouldn’t trees have ways of sending messages?

1.When attacked, a window tree will protect itself by ________.

A. changing its leaves’ chemistry B. changing its leaves’ colour

C. talking to caterpillars D. sending out a special vapour

2.From the passage we know that caterpillars _________.

A. like willow trees B. enjoy eating fallen leaves

C. feed on willow tree leaves D. could communicate with willow trees

3.Caterpillars will stop eating willow trees leaves which   __________   .

A. have a chemical change and become tasteless B. have a pleasant taste

C. are being attacked D. are communicating

4.According to the passage, how do willow trees communicate with each other ?

A. They talk in words. B. They send out a special vapour.

C. They wave their leaves. D. they make special sounds.

People can produce fresh water from the sea now.

A. steal B. make C. collect

A psychologist（心理学家） walked around a room while teaching stress management to the audience. As she raised a glass of water, everyone expected they’d be asked the “half empty or half full” question. Instead, with a smile on her face, she asked: “______?”

Answers came out from 8 oz（盎司） to 20 oz.

She replied, “The real weight doesn’t matter. It depends on how long I hold it. If I hold it for a minute, it’s not a problem. If I hold it for an hour, I’ll have an ache in my arm. If I hold it for a day, my arm will feel numb. In each case, the weight of the glass doesn’t change, but the longer I hold it, the heavier it becomes.”

She continued, “The stresses and worries in life are like that glass of water. Think about them for a while and nothing happens. Think about them a bit longer and they begin to hurt. And if you think about them all day long, you will feel numb-unable to do anything.”

It’s important to remember to let go of your stresses. As early in the evening as you can, put all your burdens down. Don’t carry them through the evening and into the night. Remember to put the glass down!

1.Which of the following can be put at the end of the first paragraph?

A. How much is this glass of water?

B. How heavy is this glass of water?

C. How long can I hold this glass of water?

D. How soon can I drink this glass of water?

2.According to the passage, people often feel bad when having stresses because ______.

A. they think about them for a while

B. they think about them for an hour

C. they think about them too often

D. they think about them too long

3.The writer expressed his opinion through ______.

A. talking an example B. giving a fact

C. having a discussion D. telling a story

4.Which of the following can be the best title of the passage?

A. Let go of your problems.

B. Let’s think of our worries for a while.

C. Let go of you stresses

D. Let’s put down our glasses of water.

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