(C)The earth is not only, but also thirsty for water. This may seem strange to you. because nearly 70% of the earth’s surface（表面）is covered with water. But about 97% of that is sea water, or salt water. Man can only use the other 3%—the fresh water from rivers, lakes, and other sources. And we can’t even use all of that, because some of it is in the form of icebergs and glaciers（冰川）. Even worse, some of it has been polluted.
However, as things stand today, the fresh water is still enough for us. But our need for water is becoming larger and larger quickly—almost day by day. We should take steps to do with this problem now and in this way we can get away from a serious world-wide water shortage later on.
We all have to learn how to stop wasting our valuable water, one of the first step is to develop ways of reusing it. Today in most large cities, water is used only once and then sent out into a sewer system(下水道), from there it returns to sea or runs into underground (地下)places.
But even if every large city reused its water, we still would not have enough. All we’d have to do to make use of sea water in the world is to remove the salt.
小题1: The earth is thirsty for water because_______ .
A．man has not enough food to eat.
B．we haven’t had enough fresh water
C．only 70% of the earth’s surface is covered with water.
D．more water is sent into the sewer system小题2:The underlined word “valuable ” means _______. .
A．much and salt
B．fresh and enough
C．dear and useful
D．clean and helpful小题3: What can we do if we want to have enough fresh water?
(a) make good use of the sea water.
(b) carry salt water into lakes and rivers.
(c) try to save the fresh water as much as possible
(d) do our best to use the water again.
(e) drink and use all the water on the earth’s surface
A．(c)and(e)
B．(a) and (b)
C．(a), (c)and(d)
D．(b) , (d) and(e)小题4: The best but the most difficult way to solve the water problem of the world is to ___
A．remove the salt from the sea water
B．make the water in the cities clean.
C．take the water from underground
D．make the need for the water smaller.小题5: What is the best title for this passage?
A．The Importance of Water
B．The World’s Water Problem
C．The Thirsty World
D．Fresh Water and Sea Water
