2008考研英语全题型高分强化教程(18)

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Ⅰ Cloze

Is there a population problem?

My answer   1   the question is "YES", there is a problem. The scale of human activities is now so __2__ that we are appreciably 3 the climate and ecosystems in the U.S. and the world.

The total impact of people __4__ the environment is proportional __5__ each of two factors:

A) The number of people, and

B) The _6___ impact of each person.

If we are to_ 7___ the total impact of people on the global environment, we must address the first, or preferably both, of these  __8__.

There are many strong forces that will cause ___9_ growth of the average impact of each person on the global environment. To the  __10__ that people in underdeveloped countries  __11_ increase their material standard of living to levels more like ours, material consumption per capita will grow. So we are left __12__ the imperative of halting population growth, and then of  __13__ the question, "Can this stable population be sustained?"

To gain a better  __14__ of the seriousness of the problem, let us review some very elementary  __15__. Let us consider a   __16__ that is experiencing steady growth  _17___ such as 5% per year.

First we note that this growing quantity will double   _18__ in a   __19__ time. This _20___ time is found by dividing 70 by the percent growth per year. For example, the doubling time for a steady growth rate of 5% per year is 70 / 5 = 14 years.

Second, we note that a few doublings can give enormous numbers. It is convenient to 20  remember that ten doublings causes the growing quantity to increase in size by a factor of approximately 1000: twenty doublings will cause an increase by a factor of 1,000,000, etc.

1. [A]of              [B]to              [C]with               [D]for

2. [A]large            [B]big             [C]small              [D]little

3. [A]effecting         [B]causing         [C]affecting            [D]affiliating

4. [A]with            [B]of               [C]to                 [D]on

5. [A]of              [B]to              [C]within              [D]for

6. [A]average         [B]averagenal       [C]averaged            [D]averaging

7. [A]decrease         [B]reduce          [C]decline             [D]deduce

8. [A]truths           [B]facts            [C]factors             [D]elements

9. [A]continued        [B]continuous       [C]continual           [D]continuity

10. [A]scale           [B]extent           [C]range              [D]sphere

11. [A]seek to          [B]seek            [C]seek after           [D]seek for

12. [A]of              [B]by              [C]as                [D]with

13.[A]learning         [B]studying          [C]searching          [D]researching

14.[A]appreciation      [B]understanding      [C]awareness         [D]knowledge

15.[A]arithmetician     [B]arithmetically       [C]aristocratic        [D]arithmetic

16.[A]amount          [B]quality           [C]quantity           [D]number

17. [A]on a rate         [B]at a rate          [C]of a rate           [D]at rate

18.[A]in size            [B]in number        [C]in amount         [D]in measurement

19.[A]given            [B]suggested         [C]fixed             [D]little

20.[A]double            [B]doubling         [C]doubled           [D]doubles