Rivers are one of our most important natural resources. Many of the world’s great cities are ______ (locate) on rivers, and almost _______ country has at least one river flowing through it that plays ________ important part in the lives of its people.
Since the beginning of history, people _______ (use) rivers for transportation. The longest one in the United States is the Mississippi, and the lifeline of Egypt is the Nile. _________ transportation, rivers give water to drink, water for crops, and chances for fun and recreation for the people ______ live along their banks.
However, large cities and industries that are located on rivers often make problems. As the cities grow _______ size and industries increase in number, the water in the rivers becomes ________ (pollute) with chemicals and other materials. People are learning the _________ (important) of doing more to keep their rivers clean ________ they want to enjoy the benefits of this natural resource.

科目 英语   题型 填空题   难度 中等

知识点： 语法填空