Rivers are one of our most important natural resources. Many of the world’s great cities are located on rivers, and almost __1_______ country has at least one river __2_______(flow) through it that plays __3________ important part in the lives of its people.

Since the beginning of history, people _4______________ (use) rivers for transportation. The longest one in the United States is the Mississippi, and the lifeline of Egypt is the Nile. __5_____________ transportation, rivers give water to drink, water for crops, and chances for fun and recreation （消遣，娱乐活动）for the people __6________________ live along their banks.

However, large cities and industries that are located on rivers often make problems. As the cities grow __7____________ size and industries increase in number, the water in the rivers becomes __8_____________ (pollute) with chemicals and other materials. People come to kwon the __9_____________ (important) of doing more to keep their rivers clean __10_____________ they want to enjoy the benefits of this natural resource.    

    Rivers are one of our most important natural resources. Many of the world’s great cities are located on rivers, and almost __1_______ country has at least one river __2_______(flow) through it that plays __3________ important part in the lives of its people.

    Since the beginning of history, people _4______________ (use) rivers for transportation. The longest one in the United States is the Mississippi, and the lifeline of Egypt is the Nile. __5_____________ transportation, rivers give water to drink, water for crops, and chances for fun and recreation （消遣，娱乐活动）for the people __6________________ live along their banks.

    However, large cities and industries that are located on rivers often make problems. As the cities grow __7____________ size and industries increase in number, the water in the rivers becomes __8_____________ (pollute) with chemicals and other materials. People come to kwon the __9_____________ (important) of doing more to keep their rivers clean __10_____________ they want to enjoy the benefits of this natural resource.    

Rivers are one of our most important natural resources. Many of the world’s great _____31____ are located on rivers, and almost ____32_____ country has at least one river flowing through it that plays _____33_____ important part in the lives of its people.

   Since the beginning of history, people _____34_____ (use) rivers for transportation. The longest one in the United States is the Mississippi, and the lifeline of Egypt is the Nile. _____35_____ transportation, rivers give water to drink, water for crops, and chances for fun and recreation for the people ____36___ live along their banks.

   However, large cities and industries that are located on rivers often make problems. As the cities grow ____37_____ size and industries increase in number, the water in the rivers becomes _____38_____ (pollute) with chemicals and other materials. People are learning the _____39_____ (important) of doing more to keep their rivers clean ____40______ they want to enjoy the benefits of this natural resource.

阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空，并将答案填写在答题卡标号为31－40的相应位置上。

Rivers are one of our most important natural resources. Many of the world’s great ________ are located 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.

阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空，并将答案填写在答题卡标号为31－40的相应位置上。

Rivers are one of our most important natural resources. Many of the world’s great ____1.____ are located on rivers, and almost ___2.____ country has at least one river flowing through it that plays ____3.____ important part in the lives of its people.

Since the beginning of history, people _____4._____ (use) rivers for transportation. The longest one in the United States is the Mississippi, and the lifeline of Egypt is the Nile. _____5._____ transportation, rivers give water to drink, water for crops, and chances for fun and recreation for the people ___6.___ live along their banks.

However, large cities and industries that are located on rivers often make problems. As the cities grow __7.____ size and industries increase in number, the water in the rivers becomes ____8._____ (pollute) with chemicals and other materials. People are learning the ___9._____ (important) of doing more to keep their rivers clean ___10._____ they want to enjoy the benefits of this natural resource.