题目内容：

Sales of laptop computers passed desktops in the U.S. for the first time ever this fall, according to market-research firm IDC. That's bad news for backs, necks and shoulders.

Laptops are bad for our body. When you work at a computer, the keyboard should be at elbow height and the monitor should be roughly at eye level, so you can sit well in a chair. But most users simply set their laptops on a desk or table. The keyboard is too high, which makes your arms reach up, your shoulders feel tired and your wrists bend down. The monitor is too low, which pulls your head and neck forward and down and your back may feel hurt.

That's OK if you use your laptop for a short time. But if you use one for hours without stopping – as do millions of college students, business travelers, telecommuters, video-gamers and growing numbers of office workers – your body may feel hurt. Ergonomics experts have warned about laptop problems for years. But people still like laptops better than the desktops. And they use laptops anywhere – in bed, on the floor – in all kinds of positions.

“How can a mouse or a keyboard hurt you?” says Thomas Caffrey, the founder of Myofactors LLC, “Wrong positions can be bad for your body. As time goes by, a wrong position can lead to pain in the neck, shoulders, back and arms, as well as headaches.”

1.When you work at a computer, the keyboard should be ________.

A．at elbow height	B．at eye height
C．on a desk	D．on a table

2.The writer asks us not to use the laptop ________.

A．for a short time	B．to play video games
C．for hours without stopping	D．to buy things on the Internet

3.From the passage, we know that laptop computers ________.

A．are not so popular as the desktops

B．are more popular than the desktops

C．are not bad for our body

D．have no mouse now

4.Using a laptop in a wrong position may make ________.

A．people’s sight lower	B．people have cancer
C．people’s arm longer	D．people feel pain in the body

5.According to the passage, which of the following is NOT true?

A．When you use a laptop, you should put your monitor at eye height.

B．Laptop computers sold more than desktops this autumn.

C．To keep healthy, you should use laptop computers.

D．Business travelers often use the laptop computers for a long time.