阅读理解。
The classical study of family size and IQ was conducted in the Netherlands. It was based on the military
examinations of more than 386,000 Dutchmen. Researchers found that the brightest subjects came from the
smallest families and had few, if any, brothers and sisters when they were born. Thus the firstborn child in
a family of two was usually brighter than the last child in a family.
The effects of family size on intelligence (智力) may be explained by what a house full of children does
to the home environment. It increases the amount of time a child spends with other children and decreases
the amount of parental attention he or she receives. For example, a parent with one restless child is likely to
sit and play with the child. The same parent with two or three restless children is more likely to ask them to
play with each other. Some psychologists say that when a child interacts (交往) with an adult alone, the child
learns more and therefore intelligence is increased. Researchers have also found that parents often expect more
from their first-born, which motivates (激发) such children to seek a higher standard.
Not all psychologists agree that firstborns tend to be more intelligent. They say that the data need to be
examined more closely for other possible explanations. For example, in industrialized nations most large
families come from lower socio-economic backgrounds. Thus environment, not family size or birth order,
may be influencing intelligence. On the other hand, there may be genetic variations (基因突变) within families
that also explain the cause of differences.
If firstborns have advantages in the area of intelligence, research has also shown that they may be more
conforming (墨守陈规) and have poorer social skills than their younger siblings (brothers and/or sisters).
Although more research needs to be done in this area, it is clear that such factors as birth order, the order in
which boys and girls are born into a family, the number of years that separate siblings probably have an effect
on the development of intelligence, personality, and social relationships.
1. The underlined word "subjects" in the 1st paragraph means _____. [ ]
A. branches of knowledge
B. persons chosen to be studied in experiments
C. citizens of a country
D. things talked about in a conversation, discussion or book
2. According to the research, usually the elder in a two-child family is _____. [ ]
A. cleverer than the younger
B. no cleverer than the younger
C. less clever than the younger
D. as clever as the younger
3. Why are firstborns encouraged to seek a higher standard? [ ]
A. They are more likely to obey others.
B. Their parents spend less time with other children.
C. They are more conforming.
D. Their parents expect more from them..
4. The best title for this passage would be _____. [ ]
A. Family Size and IQ
B. Boys Cleverer Than Girls?
C. The Development of Intelligence
D. Factors Influencing IQ
