题目内容
听力原文： Before a new airliner goes into service, every part of it is tested again and again. But there are more important than all others. One of them is very strange and the other is very dangerous.
The first of these is called the "tank test". A modern airliner usually flies at very high altitudes. Air must be pumped into the plane so that the passengers can breathe. The metal structure of the plane has to be very strong for this reason. When the plane is filled with air, the air presses against the skin of the plane. The pressure on a small window, for example, is like a huge, giant foot that is trying to get out. If a small part of the plane were to crack, the plane would explode in the sky. This is what happened to the first Comets. In order to test the structure of the plane, it is lowered into a huge tank of water. Then it is filled with air. The pressure inside the plane is greater than it ever will be when it is in the air. Finally, there is an explosion. This doesn’t cause so much damage inside the water tank as it would anywhere else. Engineers can discover which part of the plane cracked. This part is made stronger.
The most dangerous test happens when the new plane goes through test flights in the air. The test pilot must find out exactly what happens when the engines are shut off suddenly. He takes the plane up very high, and then he shuts the engines off. The plane begins to fall like a stone. It is the pilot’s job to find out how he can get control of the plane again. These two tests are examples of how planes are made safe before they ever carry passengers.
What is the purpose of the tank test？
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Part A
Directions: Read the following four texts. Answer the questions below each text by choosing A, B, C or D . Mark your answers on ANSWER SHEET 1.
Looking back on my childhood, I am convinced that naturalists are born and not made. Although we were all brought up in the same way, my brothers and sisters soon abandoned their pressed flowers and insects. Unlike them, I had no ear for music and languages. I was not an early reader and I could not do mental arithmetic.
Before World War I we spent our summer holidays in Hungary. I have only the dim memory of the house we lived in, of my room and my toys. Nor do I recall clearly the large family of grandparents, aunts, uncles and cousins who gathered next door. But I do have a crystal-clear memory of the dogs, the farm animals, the local birds, and above all, the insects.
I am a naturalist, not a scientist. I have strong love of the natural world and my enthusiasm had led me into varied investigations. I love discussing my favourite topics and enjoy burning the midnight oil reading about other people’s observations and discoveries. Then something happens that brings these observations together in my conscious mind. Suddenly you fancy you see the answer to the riddle, because it all seems to fit together. This has resulted in my publishing 300 papers and books, which some might honour with the title of scientific research.
But curiosity, a keen eye, a good memory and enjoyment of the animal and plant world do not make a scientist: one of the outstanding and essential qualities required is self-discipline, a quality I lack. A scientist, up to point, can be made. A naturalist is born. If you can combine the two, you get the best of both worlds.
The first paragraph tells us the author ______.
Not until ten o' clock______it was too late to return.
A．plantB．situationC．surroundingsD．circumstance
______born in Chicago, the writer is most famous for his stories about New York City.
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