液压缸是利用油液的()驱动机械对象实现()运动的执行元件。

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问题:

液压缸是利用油液的()驱动机械对象实现()运动的执行元件。

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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.”

小题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小题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小题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小题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小题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.

题型:填空题

排序时如果选取了多个字段,则结果是按照( )。

A.最左边的列开始排序

B.最右边的列开始排序

C.从左向右优先次序依次排序

D.从右向左优先次序依次排序

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下列胆道T管的护理,哪项不妥()

A.妥善固定

B.保持通畅

C.每日按时冲洗

D.每日更换引流瓶

E.记录引流量和性质

题型:填空题

人工呼吸的方法有种。

A、3

B、4

C、5

D、6

题型:填空题

我国古代和近代土地所有权制度自成体系,土地私有制形成期是()时期。

A.封建社会

B.奴隶社会

C.原始社会

D.半殖民地半封建社会

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