阅读下面短文，把A~D四个句子填入文中空缺处（1~4）, 使短文内容完整正确，然后完成第5题。
Babies sleep for up to eighteen hours a day. Sleep, no one can live without it. 1______
Research (研究) by the National Sleep Foundation in Washington says that we all need eight hours' sleep
every night. Scientists have found that people who sleep for less than six and a half hours a night are more
often ill than people who sleep for eight hours. 1______ "Workaholics (工作狂)" who sleep for less than five
hours often die young, and do less well at work.
It also says that the idea that we need less sleep as we get older is untrue." People have no idea how
important sleep is to their lives," Dr Thomas Roth, director of the Foundation says," 3______ "
"But not too much of it," says Professor Jim Horne." Sleep is like food and drink," he believes:" 4______
" Professor Horne studied a group of people who could spend as hours as they wanted in bed; after ten hours
they didn't find it any easier to get up in the morning. And people who sleep for more than nine hours a night
die younger than people who usually sleep for seven or eight.
A. But how much do we really need?
B. You would always like to have a little bit more, but that doesn't mean you need it.
C. Good health needs good sleeps.
D. Going without sleep also increases the chance of illness.
5. What's the best title for this passage?
A. Children and Sleep
B. The Secrets of Sleep
C. Sleep and Work
D. Are You Having Enough Sleep?
