江苏省运河中学 傅士虎
21. My chemistry teacher says that many chemical theories rest on _________ but people accept
them only when they are proven right in experiments and practice.
A. assumptions B.descriptions C. proposals D. definitions
22. ----The concert we attended last night was really marvelous.
----Yeah, I had never been to _________________.
A. the best one B. a better one C. a worst one D. the worst one
23. ---Your noodles taste nice.
---Thank you. In our culture, we _____ them to symbolize a long life.
A. are eating B. eat C. ate D. have been eating
24. A good tourist guide knows that you _____ a hotel room when you travel to another city,
even if you don’t ask.
A. have required B. would be required C. will require D. would have required
25. ---It was a hard job but thank God ,we managed to get it finished just on time.
---We were really struggling. Any relaxation ________the deadline.
A. would miss B. missed C. had missed D. would have missed
26.----I was such a disappointment. I lost a game that I shouldn't have.
----Take it easy. __________today. But bad luck won't always come.
A. It's just not your day B. you did a good job
C. you are just not yourself D. you were just nervous
27. I am sorry the sitting-room is in such a mess, but actually we___________ it for the coming
Christmas.
A. decorated B. have decorated C. decorate D. have been decorating
28. It is reported in the national newspaper that the central budget will ______ 3.5
billion yuan
for the education reform of this year.
A. distribute B. allocate C. spread D. deliver
29. Night had already fallen when we left the station. Tired and hungry, we decided to_____ for the
night at a small hotel nearby.
A. put through B. put down C. put up D. put in
30. People just don't understand why he quit the job _____he was so well paid in that big company.
A. if B. until C. once D. when
31. An important parents' meeting ______ tomorrow, all the class are busy cleaning the room
and putting some flowers on the desks.
A. given B. to be given C. giving D. will be given
32. Mr. Lopez, _____ as a manager for many years, found it hard to become an
ordinary clerk again.
A. having worked B. worked C. to have worked D. working
33. ---Any special regulations about using the lab?
---They require in no case______ it with our own clothes on.
A. can we enter B. we can enter C. should we enter D. we should enter
34. ---Do you know _____ they raised so much money within such a short time?
---They invited rich businessmen to visit poor families in person.
A. why B. when C. how D. where
35. ---Shall we go to the beach for a picnic today?
---Yes, ________ The day is beautiful and the wind is soft and warm.
A. That's all right. B. Why not? C. It doesn't matter D. So what?
答案：ABBCD ADBCD BACCB
(科技）
Freeze-drying is a technique that can help to provide food for astronauts. But it also has other applications nearer home.
The technique basically involves removing almost all the water from some material, such as food, while leaving the rest of the material untouched. The main reason for doing this is either to preserve the food or to reduce its weight. Removing the water from food keeps it from spoiling, because the microorganisms such as bacteria that cause spoiling cannot survive without it.
Freeze-drying significantly reduces the total weight of the food because most food is largely made up of water; for example, many fruits are more than 80-90% water. Removing this makes the food much lighter and therefore makes transportation less difficult.
The process is also used to preserve other sorts of material, such as medicines. Chemists can greatly extend medicine shelf life by freeze-drying the material and storing it in a container free of oxygen and water. Similarly, research scientists may use freeze-drying to preserve biological samples for long periods of time. Even valuable manuscripts that had been water damaged have been saved by using this process.
Freeze-drying is different from simple drying because it is able to remove almost all the water from materials, whereas simple drying techniques can only remove 90-95%. Most importantly, the composition of the material is not changed, so materials can be revitalised without compromising the quality of the original.
This is possible because in freeze-drying, solid water --ice -- is converted directly into water vapour, missing out the liquid phase entirely. This is called 'sublimation', the shift from a solid directly into a gas. Just like evaporation, sublimation occurs when a molecule（分子） gains enough energy to break free from the molecules around it. Water will sublime from a solid (ice) to a gas (vapour) when the molecules have enough energy to break free but the conditions aren't right for a liquid to form. These conditions are determined by heat and atmospheric pressure. When the temperature is above freezing point ice can thaw, but if the atmospheric pressure is too low for a liquid to form (below 0.06 atmospheres (ATM)) then it becomes a gas.
1. According to the passage, freeze-drying is mostly used for __________.
A. making things frozen so that they can keep fresh for long
B. storing, preservation and easier food transportation
C. keeping medicine effective in the damp environment
D. drying water out of food for further production
2. What's the most remarkable difference between freeze-drying and simple drying?
A. Freeze drying is done by freezing while simple drying is done by heating.
B.Freeze drying removes all the water while simple drying removes most water.
C. Freeze drying keeps the composition of the material while simple drying doesn't.
D. Freeze drying kills all the microorganisms while simple drying just kills bacteria.
3. In freeze-drying, what makes it possible for ice to turn into gas directly?
A. Proper temperature and low atmospheric pressure.
B. Low temperature and high atmospheric pressure.
C. High temperature and high atmospheric pressure.
D. Low temperature and proper atmospheric pressure.
4. Which of the following is closest in meaning to the underline word \"revitalized\"
A.relieved B. reproduced C. reduced D. restored
答案：BCAD
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