"I'm going to bed earlier tomorrow! "But no matter how we decide， there are still many chances that we break our promises．

This behavior is called" bedtime procrastination"（睡眠拖延症）， and results from being short of self﹣control and our body clock．

Bedtime procrastination is a common problem． According to a study， Among 2， 400 people， 53 percent of them couldn't follow their sleeping time they had planned， delaying（#fE R ）it at least twice a week． They delayed bedtime not because they liked to stay up late， but they couldn't stop doing some other things．

Accordingly， People who usually have trouble resisting temptations（抵制诱惑） and adhering to their intentions（坚持己见） are more likely to delay going to bed．

However， scientists think being short of self﹣control is not the only problem． Our body clock also lays an important role when it comes to bedtime．

In order to check the influence of the body clock on sleep， scientists studied the sleep patterns （t模式）of 108 people． It was found that those who got up late are more likely to delay their bedtime than those who woke up early every morning．

And more surprisingly， night owls（夜猫子）would go to bed late at the very beginning of the weekday， even though they had to get up early for work and school． It's their special body clock that plays a part in delaying their bedtime．

People always think that bedtime procrastination isn't a big problem， but the choices we make that affect （影响）our sleep could finally be pretty important for our health．

根据短文内容，选择最佳答案．

（1）Bedtime procrastination is partly because of 　　．

A．	being short of self﹣control．
B．	resisting temptations．
C．	adhering to their intentions
D．	working hard

（2）Bedtime procrastination is a common problem because 　　．

A．	people liked to stay up late
B．	people have trouble going to bed
C．	over 50% of people couldn't sleep on time
D．	people are night owls

（3） 　　people were tested on the sleeping influence of the body clock．

A

A．	．2400
B．	53 percent of
C．	47 percent of
D．	108

（4）According to the passage， which of the following is NOT true？ 　　

A．	People who got up late are more likely to delay their bedtime．
B．	People who woke up early may not delay their bedtime．
C．	Night owls always got up late．
D．	Night owls delayed their bedtime due to their special body clock．

（5）The writer implies（ 暗示）that bedtime procrastination 　　．

A．	is not a big problem
B．	has no any influence on our body
C．	is the choice we make
D．	is harmful