根据短文内容及首字母提示，填写所缺单词，使短文意思完整。每空限一词。

Air is very important to everything that lives. But the air we breathe is g  1.   dirty. People all over the world are looking for w  2.   to make it clean again.

Have you ever watched the smoke from chimneys(烟囱) r  3.   high in the air? Have you s   4.___ the smoke from cars and trucks on roads or the smoke from planes? The smoke is h  5.   to everyone, especially old people and children. If we want to keep well and strong, we need to breathe f  6.   air.

With more and m   7.   factories everywhere and more and more cars, trucks and planes, it is getting harder and harder to do with the air p  8.   .

Scientists have a 9.   found ways to stop or slow down some of the things that make the air dirty. They will not stop working u  10.  we have clean air again.

The American expression “shoo-in” means someone or something that seems sure to win a race or competition.
Before a big football game, supporters of each are certain to argue about which side will win.
Sometimes, however, one team appears so much stronger than the others that everyone agrees it will win.. The stronger team is a shoo-in. There is no way that it can lose.
The expression “shoo-in” comes from horse racing. It comes from the world “shoo”. That is not the shoe we wear on our feet. It’s another word, S-H-O-O. To shoo is an expression hundreds of years old that means to force an animal to move in a desired direction.
Many years ago dishonest riders sometimes agreed secretly to control their horses so that one chosen horse would win the race. but one of the riders would hold back their horses. The chosen rider would shoo his horse ahead of the others, and win the race.
The other riders would secretly bet large amounts of money that the chosen horse would win. The public soon learned about such about such race. They began to call the winners of such a race a “shoo-in”
These days, people use shoo into describe any athlete or competition that seems certain to win, even without cheating.
American runner Edewin Moses won more than hundred races before he ran the hurdle race in the 1984 Olympic Games. Everyone said Moses was a shoo-in, and that he could not lost. And they were right. He won the gold medal.
阅读上面的短文，从每题所给的四个选项中，选出一个最佳答案
【小题1】One of the dishonest riders was sure to win the race because_______.

The American expression “shoo-in” means someone or something that seems sure to win a race or competition.

Before a big football game, supporters of each are certain to argue about which side will win.

Sometimes, however, one team appears so much stronger than the others that everyone agrees it will win.. The stronger team is a shoo-in. There is no way that it can lose.

The expression “shoo-in” comes from horse racing. It comes from the world “shoo”. That is not the shoe we wear on our feet. It’s another word, S-H-O-O. To shoo is an expression hundreds of years old that means to force an animal to move in a desired direction.

Many years ago dishonest riders sometimes agreed secretly to control their horses so that one chosen horse would win the race. but one of the riders would hold back their horses. The chosen rider would shoo his horse ahead of the others, and win the race.

The other riders would secretly bet large amounts of money that the chosen horse would win. The public soon learned about such about such race. They began to call the winners of such a race a “shoo-in”

These days, people use shoo into describe any athlete or competition that seems certain to win, even without cheating.

American runner Edewin Moses won more than hundred races before he ran the hurdle race in the 1984 Olympic Games. Everyone said Moses was a shoo-in, and that he could not lost. And they were right. He won the gold medal.

阅读上面的短文，从每题所给的四个选项中，选出一个最佳答案

1.One of the dishonest riders was sure to win the race because_______.

2.The reason why American runner Edewin Moses was regarded as a

“Shoo-in” is _________.

3.Which is the following statement is not true?

4.The main idea of the passage is that “shoo-in” is_______.

5.In the last paragraph the author means to tell us ________.