题目内容：

    Having an older brother comes with plenty of benefits. However, a new study finds an interesting downside: children with older brothers take longer when it comes to developing language skills.

The study, conducted by a group of researchers in Paris, France, builds upon early research that having older brothers is associated with poor linguistic(语言的)development. Now, researchers say they have come to a more specific conclusion: only children with an older brother show these linguistic difficulties. One would assume(假设) that children with older brothers would grow up around more conversation on a daily basis, thus speeding up their language development. But researchers say such children actually take longer than their older brothers to begin developing these skills. Researchers studied more than 1,000 children from birth to the age of five-and-a-half years old. Each child’s language skills were tested at ages 2, 3, and 5.5, using tests specially designed to measure many aspects of language development such as vocabulary and syntax(句法). What the research team discovered was significant: children with an older brother had, on average, a two-month delay in their language development compared to studied children with an older sister. As far as explaining this phenomenon, researchers have given two assumptions. The first is that older sisters tend to talk more often than older brothers, which would make up for parents being less present than they were for their first child. The second assumption is that older sisters usually compete with their brothers and sisters less than older brothers for their parents’ attention.

So far, the study’s authors say they can’t say for certain why children with older brothers have a harder time developing language skills. In the future they’d like to investigate it further.

1.What does the word “downside” mean in the first paragraph?

A.slide. B.advantage.

C.upside down. D.disadvantage.

2.What can be learned from the passage?

A.Children with older brothers will speak earlier.

B.No one knows exactly the reason why children with brothers speak later.

C.Children with an older sister had a two-month delay in speaking.

D.Researchers studied over 1,000 children of all ages.

3.What’s the weakness for the children with older brothers?

A.The parents will never care about them any more.

B.The older brothers will always fight with them.

C.The development speed of their linguistic skills will be put off.

D.They won’t enjoy life-long close relationships with the older brothers.

4.What’s the best title of the passage?

A.Young brothers usually speak earlier?

B.Having older brothers always benefits you?

C.Parents love older brothers more?

D.Sisters often compete with brothers?