engine
sea water pump
cylinder cooler
fresh water generator
第1题:
29. The writer thinks that people in large cities should __________ .
A. stop the used water from getting into underground
B. only use the water from the rivers
C. make their used water clean again
D. use as much sea water as possible
第2题:
A.forbidden
B.flesh
C.given
D.fresh
第3题:
B
The world is not only hungry,it is also thirsty for water. this may seem strange to you,since nearly 75% of the earth is covered with water. But about 97% of this water is sea water.Man can only drink and use the other 3% fresh water that comes from rivers,lakes,under-ground and other places. And we cannot even use all of that,because some of this fresh water has been made dirty.
At the moment,this small amount(数量) of fresh water is still enough for us. However,our need for water is getting greater and greater. Only if we take steps to solve this problem now,we can get away from a serious world water shortage later on. The people of the world cannot have an enjoyable life without enough clean water.
On one hand we should stop wasting this little water of ours,on the other hand we should find ways to reuse it,but this has not been done widely.
Today,in most large cities,water is used only once and it then returns to the sea or runs into underground places.lf we can make it clean again,it can be used once more just as if it were fresh from a spring.
But even if large cities reuse its water,we still would not have enough in the future. Where.could we turn to next for water? To the ocean! How can we do to make use of this great a-mount of sea water? We can take the salt from the water to make it fresh.
So if we take all these steps,we'll be in no danger of drying up!
( )26. Why does the writer say that the world is thirsty for water?
A. The amount of fresh water is really very small.
B. The people of the world waste too much water.
C. The people of the world have to drink a lot of water every day.
D. There are too many people in the world needing water.
第4题:
第5题:
After being launched from a vessel, totally enclosed survival craft which have been afloat over a long period require ______.
A.frequent opening of hatches to permit entry of fresh air
B.regular checks of bilge levels
C.use of ear plugs to dampen engine noise
D.frequent flushing of the water spray system with fresh water
第6题:
30. In order to solve the problem of water shortage,we' have to________.
a. make use of sea water on the earth
b. save as much fresh water as possible
c. reuse the water from large cities
d. stop people from,using water
e. only use the 3% of the water on the earth
A.a and e
B.a,b and c
C.b,c and d
D.a,b and d
第7题:
What is the most usual reason for the fresh water-sea water heat exchanger fouling in the sea side?
A.lube oil sludge accumulating in it
B.dirt and scale etc , formed on the surfaces
C.deformation of the tubes and the shell or the plates
D.lube oil leakage into sea-water side
第8题:
27. From the passage we know that fresh water doesn't come from________ .
A.rivers
B.lakes
C.underground
D.the sea
第9题:
第10题: