Many of the world’s pollution problems have been caused by the crowding of large groups of people into the cities. Supply for the needs of the people leads to further 1 by industry. If the rapid increase of world 2 continues at the present rate, there may be much greater 3 to human beings. Some scientists 4 of the increase in numbers of people as “population pollution（人口公害）”.
About 2, 000 years ago, the world population was about 250 million. It 5 a billion in 1850. By 1930 the population was two billion. It is now six billion. It is 6 to double by the year 2020. If the population 7 to grow at the same rate, there will be 25 billion people in the 8 a hundred years from now.
Man has been 9 the earth’s resources more and more 10 over the past years. Some of them are almost gone. Now many people believe that man’s 11 problem is how to control the 12 of the population. The material supplies in the world will be far from enough to 13 the human population if the present rate of increase continues. There is already over-crowding（过分拥挤）in many cities and 14 in some countries. Many people believe that human survival（生存） in the future 15 on the answer to the question.
1. A．progress B．pollution C．education D．production
2. A．agriculture B．industry C．environment D．population
3. A．danger B．harm C．benefit D．hardship
4. A．dream B．approve C．rid D．speak
5. A．got B．took C．brought D．reached
6. A．suggested B．hoped C．expected D．said
7. A．continues B．fails C．tries D．means
8. A．world B．country C．star D．end
9. A．discovering B．using C．digging D．destroying
10. A．seriously B．dangerously C．rapidly D．steadily
11. A．greatest B．easiest C．lightest D．simplest
12. A．existence B．start C．growth D．birth
13. A．increase B．decrease C．report D．support
14. A．discussion B．starvation C．construction D．argument
15. A．depends B．agrees C．saves D．passes
—How long is it ______ you picked up your badminton training?
—It was not until my finance became better last December _____ I started the training.
A．before; when B．until; that
C．that; when D．since; that
—Pity you missed the lecture on nuclear pollution.
—I _____it, but I was busy preparing for a job interview.
A．attended B．had attended
C．would attend D．would have attended
She was reading a book in her chair _____ first time I saw _____ old lady.
A．a; an B．the; the C．/; the D．/; an
_____ team wins on Saturday will go through to the national championships.
A．No matter what B．No matter which
C．Whatever D．Whichever
As we all know, it is usually cold in this place in January, but it _____ be warm sometimes.
A．must B．can C．should D．would
