Paris,21st November 1783. There were hundreds of people in the street round an enormous (巨大的) balloon. "What is it?" they asked.

admin2011-03-26  33

问题     Paris,21st November 1783. There were hundreds of people in the street round an enormous (巨大的) balloon. "What is it?" they asked. "What does it do?"
    Then two young men came out of a house on the other side of the street, and went to the balloon. They had some wood and paper with them, and they put it into a big basket under the balloon. Then they got into the basket. They took food with them, and some warm clothes, because it was a cold day.
    Then the two young men made a fire with the wood and paper. The fire was hot, and the hot air went up into the balloon.
    Cold air is heavy, but hot air is light and rises. After some minutes, the balloon was very light and left the ground!
    The two young men flew about five and a half miles, and came down outside the city. It wasn’t a very long journey, but it was a very important one, because it was the first journey in the air.
    Joseph and Etienne Montgolfier made this balloon. It flew because it was light, but it was dangerous because of the fire.
    Two years after that, two men crossed the English Channel from England to France in a balloon full of hydrogen. Hydrogen is a very light gas. One of them was a Frenchman, Blanchard, and the other was a rich American, Dr. John Jeffries. They had a lot of problems.
    First the balloon flew up very high, so they opened the valve (阀门) and a lot of gas came out. Then the balloon went down, so they threw everything out, even their food and clothes! But they reached France after an exciting journey, and landed near Calais(加来[法国港口城市]).
The young men’s balloon flew because the air in it was ______.

选项 A、hot
B、heavy
C、cold
D、fine

答案A

解析
转载请注明原文地址:https://kaotiyun.com/show/2YvC777K
本试题收录于: 英语题库成考专升本分类
0

最新回复(0)