Riversareoneofourmostimportantnaturalresources.Manyofth...

问题详情：

Rivers are one of our most important natural resources. Many of the world's great cities are located on rivers, and almost __41__ country has at least one river __42__(flow) through it that plays __43__ important part in the lives of its people.

Since the beginning of history, people __44__ (use) rivers for transportation. The longest one in the United States is the Mississippi, and the lifeline of Egypt is the Nile. __45__ transportation, rivers give water to drink, water for crops, and chances for fun and recreation (消遣，*活动)for the people __46__ live along their banks.

However, large cities and industries that are located on rivers often make problems. As the cities grow __47__ size and industries increase in number, the water in the rivers becomes __48__(pollute) with chemicals and other materials. People come to kwon the __49__(important) of doing more to keep their rivers clean __50__ they want to enjoy the benefits of this natural resource.   

41．______　42.______　43.______　44.______　45.______

46．______　47.______　48.______　49.______　50.______

【回答】

y/each　ing　　 used　des　　　uted　rtance　

知识点：短文填空

题型：阅读填空