The world’s population (1)________ five-billion mark in 1987 and it is increasing (2)________ about 1.7% a year. At this rate of growth, the number of people in the world will double every 41 years. This rapid increase has been called the (3)________ explosion. No one knows how many people the Earth can (4)________. Many scientists believe that the world will soon become (5)________, that is, it will have more people than it can support.  When too many people (6)________ in a small place, life can become very difficult and (7)________. In some places, there are so many people that there is not enough food or houses for everyone. Many families move to the cities, (8)________ to find work and homes. So more homes need to be (9)________. The city spreads over more and more farming land. As the world’s population (10)________, there is less and less land left for agriculture to feed all the people.

1.A.passed                         B.pass                         C.past                  D.passing

2.A.to                                 B.by                            C.in                      D.of

3.A.pollution                      B.pollut                      C.population       D.populated

4.A.be supported               B.supports                 C.supporting         D.support 

5.A.polluted       B.overpopulated      C.populated          D.overpopulation

6.A.to live                           B.living                      C.live                    D.lived

7.A.pleasant                       B.pleasing                 C.pleased               D.unpleasant

8.A.hope                            B.hoping                  C.hoped                 D.hopeless

9.A.built                            B.building                 C.build                   D.builds

10.A.grow                          B.grows                    C.grew                   D.growth

(1) passed

(2)by

(3)population 

(4)support 

(5)overpopulation 

(6)live

(7)unpleasant 

(8)hoping

(9) built 

(10)grows