54.The water in the river is polluted because of _____.

A. people’s drinking water too much　　

B. people’s swimming in the river too much

C. chemicals and other materials　　　

D. people’s building a dam across a river

53.By building a dam, people can use the water for______.

A. keeping the rivers clean　　　 B. only making electricity

C. washing clothes　　　　　　 D. irrigation and making electricity

52.Which is Wrong?

A.　　 The Nile is in India.

B.　　　 Almost every country has at least one important river.

C.　　　 Many cities are located on rivers.

D.　　 Rivers play an important part in the lives of people.

51.The greatest river for navigation is _________.

A. the Amazon　　　 B. the Nile

C. the Mekong　　　 D. the Mississippi

50. What’s the best title of the passage?

A. Rose and Hatfield: Believers in DIY.　　 B. You Can Do It ,Too.

C. The Joy of DIY.　　　　　　　　　　 D. Welcome to our DIY Course.

　　　　　　　　　　　　 (C)

Rivers are one of our most important natural resources(自然资源). Many of the world’s great cities are located on rivers, and almost every country has at least one river flowing through it that plays an important part in the lives of its people.

Since the beginning of history, people have used rivers for transportation. The longest one in the United States is the Mississippi. The lifeline of Egypt is the Nile. To the people of India , the Ganges is great. Ships can travel along it for a thousand miles. Other great rivers are the Congo in Africa and the Mekong in southeast Asia, The greatest of all for navigation(航海), however, is the Amazon in Brail, It is so wide and so deep that large ships can go about two thousand miles upon it.

Besides transportation, rivers give food, water to drink, water for crops, and chances for fun and recreation for the people who live along their banks. In order to increase the supply of water for crops, engineers sometimes build a dam(大坝) across a river and let a lake form behind the dam. Then people can use the water not only to irrigate(灌溉) their fields but also to make electricity for their homes and industries.

However, large cities and industries that are located upon rivers often make problems. As the cities grow in size and industries increase in number, the water in the rivers becomes polluted with chemicals and other materials. People are learning the importance, however, of doing more to keep their rivers clean if they want to enjoy the benefits(利益) of this natural resource.

49. Jim Hatfield decided to become a do-it-yourself when ______.

　A. he had to raise the children all by himself

B. he could not possibly do two jobs

C. the car repair class was not helpful

　D. his car repairs cost too much

48. When the writer says that Jim has a full-time job at home, he means_____.

A. he keeps the house and looks after his children

　B. he does his own car and home repairs

C. he does extra work at night

　D. he makes shoes in his home

47. John and his wife went to evening classes to learn how to _______.

　A. improve the quality of life　　 B. save time and money

　C. make or repair things　　　　 D. run a DIY shop

46. We know from the passage that many people ________.

　A. seldom go to a department store to buy things

　B. take DIY courses run (经营)by the government

　C. have to learn to make their own furniture

　D. find it hard to pay for what they need