题目内容：

When we say older people shrink,we don't mean they become tiny enough to fit in your pocket!We just mean that it's common for older people to become a little shorter over time.This kind of shrinking can't be stopped, although people can slow this process.But why does shrinking happen at all?

Because of gravity,cushions between the bones in the spine（脊骨）get compressed（压缩）,which makes a person lose a little height and become shorter.

Another reason why some older people shrink is because of osteoporosis（骨质疏松）.Osteoporosis occurs when bone is broken down and not enough new bone material is made.Over time,bone is said to be lost.Bones become smaller and weaker and can easily break if someone with osteoporosis is injured.

Older people—especially women,who generally have smaller and lighter bones to begin with—are more likely to develop osteoporosis.As years go by,a person with osteoporosis can get small breaks in bones that are called compression fractures.These breaks cause collapse of the spine and over time the person with osteoporosis can become hunched over（驼背）.

Did you know that every day you shrink a little,too?You aren't as tall at the end of the day as you are at the beginning.That's because as the day goes on,water in the disks of the spine gets compressed due to gravity,making you just a tiny bit shorter.Don't worry,though.Once you get a good night's rest,your body recovers,and the next morning,you're standing tall again!

Smoking and drinking alcohol can make this problem worse.Want to do something right now to build strong bones?I believe what I say will help you.

1.What can we infer from the text?

A. For shrinking,people can do nothing about it.

B. If someone is injured,he will become shorter.

C. Women have smaller and lighter bones than men.

D. We aren't as tall at the end of the day as we are at the beginning.

2.What should we do if we don't want to shrink faster?

A. Reduce gravity.

B. Sleep as long as possible.

C. Be careful not to be hurt by others.

D. Keep away from smoking and drinking alcohol.

3.We can learn from the text about osteoporosis that______.

A. it makes people shorter

B. shorter people usually suffer it

C. women are more likely to develop it

D. once our bone is broken down,it will occur

4.What is the best title for the text?

A. Why do we shrink?

B. How to live a healthy life

C. How can we stop shrinking?

D. Some tips on how to keep healthy