文档介绍：第四部分完形填空()
1
The population problem may be the ___1___ one of the world today. The world’s population is growing ___2__ . Two thousand years ago, there were only 250 million people ___3___ the earth. Four hundred years ago, the number was __4__ 500 million. But at the beginning of the __5__ century, the world’s population was about 1700 million. In 1970, this number was 3600 million. In 1990, the number was five billion. A __6__ report says that the world population will __7__ six billion by the end of the 20th century. This is just ten __8__ after it __9__ five billion. People say that by the year 2010, __10__ may be seven billion.
1. A. great B. greater C. greatest D. greating
2. A. faster and faster B. fast and fast C. fastest and fastest D. faster and fast
3. A. in B. on C. at D. for
4. A. close B. more C. almost D. over
5. A. twenty B. twelve C. twentieth D. twelfth
6. A. USA B. UN C. PRC D. PLA
7. A. past B. pass C. passed D. passes
8. A. weeks B. months C. seasons D. years
9. A. get B. gets C. reached D. reach
10. A. this B. its C. one D. it
CABDC BBDCD
2
You may think there is only sand in the desert of the world, but it is not true. In the desert, as we know, there is a little __1__ and it is not __2__ for most plants. Still we can see some plants live in the desert.
There is __3__in some places in the deserts. We call these places oases(绿洲). In th oases, there are villages and towns. People grow all kinds of vegetables and rice in the fields there. People __4__ live outside the oases. They have camels, sheep and other animals. These animals live __5__ the desert plants for their food and do not need any water. The animals are useful to the desert people in many ways. They eat the __6__ and drink the milk of animals. They __7__ the camels for carrying water, food and something else.
The people of the desert have to keep __8__from place to place. They must always look __9__ grass or desert plants for their animals. When there is no mo