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毛泽东在《＜共产党＞发刊词》中所说的“伟大工程”是指
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Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
What produces a waterproof super glue, acts like a vacuum cleaner, and even teaches scientists about gene repair？ The humble little shellfish known as the mussel (贻贝).
Mussels are found worldwide. Some live in the sea. Others inhabit freshwater streams and lakes. When you try to move a mussel from a rock, you will discover what an incredibly firm grip it has-a necessity if the mussel is to resist the sharp grab of a hungry seabird or the pounding waves of the sea. How does it manage to cling so tight'？ When it chooses a place to set up home, it pokes its tongue-shaped foot out of its shell and presses it against a solid surface. Special glands give off a fluid mixture of proteins into a channel that runs the length of the foot. The liquid quickly hardens into a fine, elastic thread about an inch long. Then a tiny pad-like structure at the end of this thread gives off some natural glue-like substance, the mussel lifts its foot, and anchor line number one is complete. These strategically placed threads form. a bundle, which ties the mussel to its new home in much the same way that ropes hold down a tent. The whole procedure takes only three or four minutes.
Imagine having a very strong glue that is non-toxic and so flexible that it can penetrate the tiniest holes and comers, sticking to any surface, even under water. Shipbuilders would welcome it for repairing vessels without the expense of dry-docking them. Auto-body workers would like a really waterproof paint that keeps the rust out. Surgeons would value a safe glue to join broken bones and to close wounds... The list of possible uses appears endless.
However, scientists are not thinking of using the mussels themselves to produce this super glue. It would take some 10 000 shellfish to make just one gram of glue. So collecting enough mussels to supply the world's demand for super glue would wipe out the mussel population, many species of which are already endangered. Instead, American researchers have isolated and cloned the genes for five mussel glue proteins, and they are about to mass-produce them in the laboratory. However, the mussel is still one jump ahead. Only the mussel instinctively knows the exact blend of proteins needed for each kind of surface. Molecular biologist Frank Roberto has asked admiringly:" how are you ever going to imitate that？"
A mussel grips a hard surface very firmly to ______.
When reserving a hotel room with your check card, you have to decide how much money in your account has to be on hold.
听力原文：M: Those were such funny stories Tom told last night. He was like a totally different guy.
W: Yeah, really. He is normally so serious. What do you think brought all that out of him？
Q: What does the woman imply？
(16)
听力原文：W: Roger, any problems in your Korean study？
M: The biggest problem with me is the Korean vocabulary. It really makes me frustrated. The pronunciation and usage put me into great confusion as I keep forgetting them.
W: I guess first of all you can narrow down the vocabulary sphere. I mean, try to learn "core" vocabulary, the words with high frequencies of occurrence.
M: That sounds quite reasonable. Do you think I can find in bookstores a book or dictionary where such kinds of words are listed？
W: Yes, definitely. Another thing, the first several occurrences of strange words are very important. Words are best remembered if they are learnt quickly with a few presentations. You may not have much trouble in remembering swear words, may you？
M: No. They're very impressive and quite memorable. I don't even need to practice them.
W: That's it! For other words that don't have such a strong effect, yon have to make yourself highly attentive and sensitive. If not, later practice and repetition don't seem to work so well.
M: I see.
W: The last thing I'll say is that if you want to remember something for periods longer than a year or two, you need to space the presentations over quite long intervals of days, say 30 days. A more frequent interval doesn't promise you longer remembrance.
M: Really？ I have thought every word should be practiced as often as possible within a short time span.
W: No. How the word is practiced is much more important than how often it is practiced.
M: You really do me a great favor, Teresa.
(23)
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