题目内容

The forest from which man takes his timber is the tallest and most impressive plant community on Earth. In terms of man's brief life it appears permanent and unchanging, save for the seasonal growth and fail of the leaves, but to forester it represents the climax of a long succession of events.
No wooded landscape we see today has been forest for all time. Plants have minimum requirements of temperature and moisture and, in ages past, virtually every part of Earth's surface has at some time been either too dry or too cold for plants to survive. However, as soon as climatic conditions change in favor of plant life, a fascinating sequence of changes occurs, called a primary succession.
First to colonize the barren land are the lowly lichens, surviving on bare rock. Slowly, the acids produced by these organisms crack the rock surface, plant debris accumulates, and mosses establish a shallow root-hold. Ferns may follow and, with short grasses and shrubs, gradually form. a covering of plant life. Roots probe even deeper into the developing soil and eventually large shrubs give way to the first trees. These grow rapidly, cutting off sunlight from the smaller plants, and soon establish complete domination-closing their ranks and forming a climax community which may endure for thousands of years.
Yet even this community is not everlasting. Fire may destroy it outright and settlers may cut it down to gain land for pasture or cultivation. If the land is then abandoned, a secondary succession will take over, developing much faster on the more hospitable soil. Shrubs and trees are among the early invaders, their seeds carried by the wind, by birds and lodged in the coats of mammals.
For as long as it stands and thrives, the forest is a vast machine, storing energy and many elements essential for life.
What does the forest strike mankind as permanent?

A. The trees are in community.
B. The forest is renewed each season.
C. Man's life is short in comparison.
D. It is an essential part our lives.

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听力原文: Man's first real invention, and one of the most important inventions in history, was the wheel. All transportation and every machine in the world depend on it. The wheel is the simplest yet perhaps the most remarkable of all inventions. Because there are no wheels in nature, no living things was ever created with wheels. How, then, did man come to invent the wheel?
Perhaps some early hunters found that they could roll the body of a heavy animal through the forest on logs mole easily than they could carry it. However, the logs themselves weighed a lot. It must have taken a great prehistoric thinker to imagine two thin slices of log connected at their centers by a strong stick. This would roll along just as the logs did, yet be much lighter and easier to handle. Thus the wheel and axle came into being, and with them the first carts.
(30)

A. It led to many other inventions.
B. Man had no use for it then.
C. There were no wheels in nature.
D. All of the above.

听力原文:W: Good morning. This is Mrs. Jackson. May I please speak with Dr. Ellis?
M: Dr. Ellis is speaking, Mrs. Jackson. How's that new bridge?
W: Not so good, doctor. That's what I'm calling about. It just doesn't seem to fit right.
M: Well, that's to be expected during the first few days after it has been put in. As I told you, there will be no complications.
W: It hurts so much, especially when I eat. I keep removing it afterwards, you know.
M: I understand, Mrs. Jackson. It does hurt in the beginning, I know. But it would be better if you didn't remove it, except when cleaning it, of course.
W: Well, I did at first, doctor, but my gums hurt so much that I just can't stand it any longer.
M: Well, maybe we can adjust it a little more.
W: Adjust it?
M: Yes, file it down a little here and there. When can you come in?
W: Oh, right away, doctor, if you don't mind.
M: Let me see, I'll check here now. Maybe I can find the time for you this morning.
W: Oh, I can wait until this afternoon if you you're too busy now.
M: Sorry, Mrs. Jackson, but I'd rather you'd come this morning if possible. This afternoon I'm teaching a class at the dental school. Just a minute. Mrs. Jackson, can you get here about 11:30? That will give us enough time before lunch. We'll see what we can do.
W: Oh, yes doctor, I can make it. Thank you. See you then.
(23)

A. Her false teeth wasn't fit.
B. She broken her legs.
C. Her feet were badly injured.
D. She cut her finger.

Section A
Directions: In this section, you will hear 8 short conversations and 2 long conversations. At the end of each conversation, one or more questions will be asked about what was said. Both the conversation and the questions will be spoken only once. After each question there will be a pause. During the pause, you must read the four choices marked A, B, C and D, and decide which is the best answer.
(12)

A. The man will arrive at the hotel only fourteen minutes late.
B. The man has a quarter to get to the hotel.
C. The man will certainly miss his business.
D. The woman does not think she will be able to drive quickly.

A.He failed only in physics.B.He will not pass the exam if he doesn't review his lesso

A. He failed only in physics.
B. He will not pass the exam if he doesn't review his lessons.
C. He's intelligent.
D. Clever people may be victims of their own cleverness.

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