Are some people born clever, and others born stupid? Or is intelligence (智力) developed by our environment and our experience? Strangely enough, the answer to these questions is yes. In some degree, our intelligence is given to us at birth, and no education can make a genius (天才) 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 environment. Therefore, the limits(限度) of person’s intelligence are fixed at birth, whether or not he reaches those limits will depend on his environment. This point of view, now is held by most experts.
It is easy to show that intelligence is something that we are born with. The closer the blood relationship between two people, the closer they are likely to be intelligence. If we take two strangers by chance from the population, it seems that their degree of intelligence will be completely different. If, on the other hand, we compare two twins, they will very likely be as intelligent as each other. Relations like brothers and sisters, parents and children, usually have similar intelligence, and this clearly suggests that intelligence depends on birth.
Imagine now that we take two twins and put them in different environments. We might send one, for example, to a university and the other to a factory separately where the work is boring. We would soon find differences in intelligence developing, and this shows that environment as well as birth plays an important part. This result is also suggested by the fact that people who live in close contact with each other, but who are not related at all are likely to have similar degree of intelligence.
How is man’s intelligence given?

A．At birth.

B．Through education.

C．Both at birth and through education.

D．Neither at birth nor through education.

According to the passage, if a child is born with low intelligence, what might happen to him later?

A．Become a genius.

B．Still become a genius if he should be given special education.

C．Reach his intelligence limits in rich environment.

D．Never reach his intelligence in his life.

What can we learn from the example of the twins going to a university and to a factory?

A．The importance of their intelligence.

B．The role of environment on intelligence.

C．The importance of their jobs.

D．The part that birth plays.

What statement is TRUE according to the passage?

A．No education can help make a genius.

B．Personality is important as intelligence which was given to people at birth.

C．People who have similar degree of intelligence must be relatives.

D．Environment influences people in intelligence developing.

How does the writer make his idea clear?

A．By giving explanation.	B．By giving an example.
C．By giving figures(数字).	D．By giving suggestions.