8、動(dòng)詞填空（共10空，計(jì)10分）

 閱讀下面短文，用括號內(nèi)所給動(dòng)詞的適當(dāng)形式填空(必要時(shí)可加情態(tài)動(dòng)詞或助動(dòng)詞）。

The earth is our home. We must take care of it .Life today is easier than it was hundreds of years ago, but it (61)__    (bring) some new problems. One of the biggest problems is pollution. We can see it, smell it and even hear it.

Man (62)________(pollute) the earth. The more people, the more pollution. Many years ago, the problem (63 )___    (be not) so serious because there were not so many people. When the land (64 )_____  (use) up or the river was not clean in a place, man went to another place. Now man ( 65 )_________(pollute) the whole world slowly.

Air pollution is still the most serious. it’s bad for living things in the world.

Many countries don’t let people (66 )    (burn) something bad for the air in houses and factories. Pollution by SO2 is now the most dangerous kinds of air pollution. It(67 )______(cause) by heavy traffic. People say it’s best (68)___    (ride) bikes. When you are riding, there is no pollution. But even in developed countries, most people don’t go to work by bike.

It’s not because bikes are expensive or people are tired if they ride to work. It’s because the number of cars on the roads (69 )  ____  (become) larger. So more people put away their bikes and go to work by car, then things (70 ) ___   (get) worse and worse. We should have special roads only for bikes and make it so difficult and expensive for divers to take their cars into the city that they will go back to using their bikes.

Keys: 61. has brought, 62.has polluted, 63. wasn’t 64. was used ,65.is polluting 66. burn ,67.is caused 68. to ride 69. becomes 70. are getting