(1)
A)Because they need air.
B)Because they don't carry scientific instruments.
C)Because they can only travel for hundreds of miles.
D)Because they carry animals and people. (2)
A)When the Second World War had ended.
B)Shortly after they had sent up a rocket with scientific instruments.
C)After they had sent up animals and brought them safely back to earth.
D)After they had sent the first man-made satellite. (3)
A)He traveled faster than any man had done before.
B)He didn't feel he was traveling quickly.
C)He was lying upon a couch in the spaceship.
D)He was sitting at the controls.
原文：
Passage 2
After the end of the Second World War, the Russians became very interested
in space science, and they sent several rockets up above the air. The
Earth is surrounded by air, but this sir doesn't stretch upward for more
than a few hundred miles, and above a height of only about ten miles the
air is so thin that no ordinary plane will fly in it. To go higher, it is
necessary to use a rocket, which will work excellently even when moving in
outer space. The first rockets sent up into space carried no astronauts
but scientific instruments; the next carried animals and when they were
brought safely to earth, the Russian scientists were ready to send up a
man. They chose Yuri Gagarin to be the pilot.
Flying a spaceship is not the same as flying an ordinary plane. Instead of
sitting at the controls, the pilot lies upon a couch.
The spaceship was traveling at a speed of 5 miles a second -- faster than
any man traveled before. Gagarin did not get any feeling for the speed,
and he could look through the small round window of the cabin.
Questions 15 to 17 are based on the passage you have just heard.
15. Why can't the ordinary planes travel in space?
16. When were the Russians ready to send a man into space?
17. Which of the following about Gagarin is not true?