题目内容
The world is nor only hungry，but it is also t 1 for water．This may seem strange to you，since nearly 70％of the earth is c 2 with water：But about 97％of this huge amount is sea water，or salt water．Man can only drink and use the other 3％——the fresh water from rivers，lakes，
underground，and other sources. Even w 3 ，some of it has been p 4 ．Now our need for water is i 5 -almost day by day．We must take steps to solve this prob1em，or we can’t a 6 a worldwide water shortage later on．
We all have to learn how to s 7 water．One of the first steps is to develop ways of reusing it．
Today in most large cities，water is used only o 8 and then sent out into a sewer system(下水道)．But it is possible to get used water to a purifying(净化)factory．There it can be purified so t9 it can be used again．
The world’s water shortage is a big p10 for humans．We must save every drop of water and keep our rivers and lakes clean．
试题答案
1、1．thirsty 2．covered 3．worse 4．polluted 5．Increasing
6．avoid 7．stop 8．once 9．that 10．problem
The world is nor only hungry，but it is also t 1 for water．This may seem strange to you，since nearly 70％of the earth is c 2 with water：But about 97％of this huge amount is sea water，or salt water．Man can only drink and use the other 3％——the fresh water from rivers，lakes，
underground，and other sources. Even w 3 ，some of it has been p 4 ．Now our need for water is i 5 -almost day by day．We must take steps to solve this prob1em，or we can’t a 6 a worldwide water shortage later on．
We all have to learn how to s 7 water．One of the first steps is to develop ways of reusing it．
Today in most large cities，water is used only o 8 and then sent out into a sewer system(下水道)．But it is possible to get used water to a purifying(净化)factory．There it can be purified so t9 it can be used again．
The world’s water shortage is a big p10 for humans．We must save every drop of water and keep our rivers and lakes clean．
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