A2 Complete the passage with the words and phrases in A1 in their proper forms. 用A1中单词和词组的适当形式完成短文。
Water is very important for life. About 70% of the Earth's surface (1)
is covered with
water. However, most of the water is salty, and only a small part is (2)________
fresh water
. This makes drinkable water very (3)________
rare
. Even in places where there is enough (4)________
drinking water
, the water may be (5)________
polluted
because of the waste from nearby (6)________
factories
. This makes it unsuitable to drink.
Some scientists say that by 2050, over 2 (7)
billion
people may not (8)________
reach
clean drinking water. One possible way to deal with it is to (9)"________"
lock up
our drinking water, which means to store it safely, and also keep it clean. If we don't do so, the (10)________
rest
of the world's water may become too scarce (缺乏的) and too dirty for drinking.
