[单项选择]Some people waste food, ______ others haven't enough.
A. since
B. because
C. while
D. if

[单项选择]Despite technical progress, some food production is still completely ______ on weather.
A. reliable
B. dependable
C. dependent
D. inseparable

[单项选择]

Passage 1
Are some people born clever and others born stupid Or is intelligence developed by our environment and our experience Strangely enough, the answer to these questions is yes. To some extent our intelligence is given us at birth. On the other hand, a child who lives in boring environment will develop his intelligence less than one who lives in rich and varied surroundings. Thus the limits of a person’ s intelligence are fixed at birth, whether or not he reaches those limits will depend on his environment. This view, now held by most experts, can be supported in a number of ways.
It is easy to show that intelligence is to some extent something we are born with. The closer the blood relationship between two people, the closer they likely to be in intelligence. Thus if we take two unrelated people at random from the population, it is likely that their degree of intelligence will be completely different. If,on the other hand, we take two identical
A. never become a genius
B. exceed his intelligence limits in rich surroundings
C. still become a genius if he should be given special education
D. not reach his intelligence in his life

[单项选择]Some people enjoy training; for others it is only a ______ to an end.


A. way
B. tool
C. method
D. means

[单项选择]

Are some people born clever, and others born stupid Or is intelligence developed by our environment and our experience Strangely enough, the answer to these questions is yes. To some extent our intelligence is given to us at birth, and no amount of special education can make a genius out of a child born with low intelligence. On the other hand, a child who lives in a boring environment will develop his intelligence less than one who lives in rich and varied surroundings. Thus the limits of a person’s intelligence are fixed at birth, whether or not he reaches those limits will depend on his environment. This view, now held by most experts, can be supported in a number of ways.
It is easy to show that intelligence is to some extent something we are born with. The closer the blood relationship between two people, the closer they are likely to be in intelligence.Thus if we take two unrelated people at random from the population, it is likely that their degree of
A. Surroundings
B. Intelligence
C. Dependence on Environment
D. Effect of Education

[单项选择]Mrs. Perry left some food for Jack because ______.