III. 完形填空：

    Many of the world's pollution problems have been 1    by the crowding of large groups of people into cities．Supply for the 2     of the people leads to 3    pollution by industry．If the 4    increase in human population 5    at the present rate（比率），there may be much greater harm． Some scientists speak of the 6    in number of people as“population pollution．”

  About 2000 years ago，the world 7   was probably about 250 million． 8    reached a billion in 1850．By 1930the population was two billion．It is 9      six and a half billion．It is 10    to double by the year 2050．If the population continues to grow at the same 11    ， there would be 25 billion people in the world a hundred years from now．

  Man has been using the earth's 12    more and more rapidly over the years．Some of them are almost 13    ．Now many people believe that man's greatest 14    is how to control the growth of his population．The 15    in the world will not support the human population，in time to come，if the 16    rate of increase continues． 17    there is over crowding in the 18    and hunger in some countries． Can man's rate of increase 19    ？Many people believe that human survival（继续生存）in the future depends on the answer 20    the question．

1．A．made  B．caused      C．led    D．worked out

2．A．needs  B．satisfies    C．service      D．lacks

3．A．farther       B．less   C．further      D．better

4．A．harmful      B．small C．slow  D．rapid

5．A．stops   B．continues  C．slows down      D．adds to

6．A．increase      B．reduce      C．quality      D．quantity

7．A．people B．situation   C．population       D．land

8．A．They   B．You   C．We    D．It

9．A．now    B．in the past C．in the future     D．then

10．A．hoped  B．expected   C．wished   D．looked forward to

11．A．time  B．year  C．rate   D．period

12．A．place B．oil     C．mines       D．resources

13．A．missed      B．rich   C．gone  D．enough

14．A．problem   B．power       C．plan  D．idea

15．A．food  B．electricity C．energy      D．materials

16．A．past   B．present     C．future       D．slow

17．A．Already    B．Yet    C．Still  D．Often

18．A．villages    B．mountains C．cities D．farms

19．A．continue   B．exist  C．fall    D．keep

20．A．in     B．of     C．to      D．for

Many of the world's pollution problems have been 1　 by the crowding of large groups of people into cities．Supply for the 2　　 of the people leads to 3　 pollution by industry．If the 4　 increase in human population 5　 at the present rate，there may be much greater harm． Some scientists speak of the 6　 in number of people as“population pollution．”

About 2000 years ago，the world 7　 was probably about 250 million． 8 　reached a billion in 1850．By 1930the population was two billion．It is 9　 three and a half billion．It is 10　 to double by the year 2005．If the population continues to grow at the same 11　 ， there would be 25 billion people in the world a hundred years from now．

Man has been using the earth's 12　 more and more rapidly over the years．Some of them are almost 13　 ．Now many people believe that man's greatest 14　 is how to control the growth of his population．The 15　 in the world will not support the human population，in time to come，if the 16　 rate of increase continues． 17　 there is over crowding in the 18　 and hunger in some countries． Can man's rate of increase 19　 ？Many people believe that human survival in the future depends on the answer 20　 the question．

1．A．made　　 B．caused　　　　 C．led　　　　　 D．worked out

2．A．needs　　 B．satisfies　　 C．service　　　 D．lacks

3．A．farther　 B．less　　　　　 C．further　　　 D．better

4．A．harmful　 B．small　　　　 C．slow　　　　　 D．rapid

5．A．stops　　 B．continues　　 C．slows down　　 D．adds to

6．A．increase B．reduce　　　　 C．quality　　　 D．quantity

7．A．people　 B．situation　　 C．population　　 D．land

8．A．They　　 B．You　　　　　 C．We　　　　　　 D．It

9．A．now　　　 B．in the past　 C．in the future D．then

10．A．hoped　 B．expected　　　 C．wished　　　 D．looked forward to

11．A．time　　 B．year　　　　　 C．rate　　　　　 D．period

12．A．place　 B．oil　　　　　 C．mines　　　　 D．resources

13．A．missed　 B．rich　　　　　 C．gone　　　　　 D．enough

14．A．problem B．power　　　　 C．plan　　　　　 D．idea

15．A．food　　 B．electricity　 C．energy　　　　 D．materials

16．A．past　　 B．present　　　 C．future　　　　 D．slow

17．A．Already B．Yet　　　　　 C．Still　　　　 D．Often

18．A．villages B．mountains　　 C．cities　　　　 D．farms

19．A．continue B．exist　　　　 C．fall　　　　　 D．keep

20．A．in　　　 B．of　　　　　　 C．to　　　　　　 D．for