Question

閱讀下面短文，根據(jù)所讀內(nèi)容在文后第53至第57小題的空格里填上適當(dāng)?shù)膯卧~或短語，并將答案轉(zhuǎn)寫到答題卡上。
注意：每空不超過3個單詞。
Each year there is an increasing number of cars as millions of new cars are produced in America. Americans will not live without cars! However, some have realized the serious problem of air pollution by cars. It is necessary to find ways to solve the problem of air pollution.
One way to clean the air is to build a new kind of clean car. That’s what several of the large car factories are trying to do. But to build a clean car is easier said than done. Progress in this field has been slow.
Another way is to take the place of the car engine by something else. Engineers are now working on it. Many makers believe that it will take years to develop a practical model for us.
To prevent the world being polluted by cars, Americans have to make some changes in the way of their life. They have to cut down on the number of their cars and are encouraged to travel and go to work by bike. But this change does not come easily ---- many workers may find themselves without jobs if a car factory closes down. And the problem of their pollution would become less important than that of unemployment.
Americans may live a happy but sad life for a long time because of the car problem..
Cars and Pollution in American

Problem	Methods	Disadvantages	57.____________
53.______________	Building a new kind of clean car.	Progress in this field is slow.	Americans may live a happy but sad life.
		It takes years to develop a 55._______
	54.________ on the number of cars	Many workers may 56.__________
	Traveling and going to work by bike.

Answer 1

53. Air pollution 
54. Cutting down   
55. practical model   
56. lose (their) jobs   
57. Conclusion

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