什么是虚拟变量陷阱？

Our surrounding(周围) is being polluted faster than nature and man’s present efforts can’t prevent it. Time is bringing us more people, and more people will bring us more industry, more cars, larger cities, and the growing use of man-made materials.

What can explain and solve this problem? The fact is that pollution is caused by man—by his desire for a modern way of life. We make “increasing industrialization” our chief aim. So we are always ready to offer everything: clean air, pure water, good food, our health and the future of our children. There is a constant flow of people from countryside to cities, eager for the benefit of our modern society. But as our technological achievements have grown in the last twenty years, pollution has become a serious problem.

Isn’t it time we stopped to ask ourselves where we are going—and why? It makes one think of the story about the airline pilot who told his passengers over the loudspeaker, “I’ve some good news and some bad news. The good news is that we’re making rapid progress at 530 miles per hour. The bad news is that we’re lost and don’t know where we’re going.” The sad fact is that this becomes a true story when spoken of our modern society.

小题1:Man can’t prevent the world from being polluted mainly because        .

A．many man-made materials

B．more cars, trucks and buses

C．more people and more industry

D．more cities小题2:People crowd into the cities because_________.

A．they want very much to find well-paid jobs

B．they eager for the achievement of our modern society

C．they have become tired of their homeland

D．they have a strong wish to become industrial workers小题3:The story about the airline pilot tells us that_________.

A．man knows where the society is going

B．people do not welcome the rapid development of modern society

C．man can do little about the problem of pollution

D．the writer is worried about the future of our society小题4:What does the writer really want to say in this passage?

A．With the development of technology, pollution has become a serious problem.

B．Lower the speed of development to stop pollution.

C．It’s time we did something to reduce pollution.

D．As industry is growing fast, pollution is the natural result.

对于仅是单一的操作、事故处理操作、拉开接地闸刀和拆除仅有的一组接地线的操作,可不填写工作票，但应记入操作记录本。

判断病人有无脉搏下列哪项是正确的（）？

A.同时触摸双侧颈动脉

B.颈动脉触摸时，不要用力过大

C.检查时间不得短于10s

D.不能触摸股动脉

E.颈动脉搏动点在胸锁乳突肌外缘

被称为“科学管理之父”的是（）

A.法约尔

B.泰勒

C.韦伯

D.梅奥

E.卢因

环境风险评价的目的是分析和预测建设项目存在的潜在危险、有害因素，建设项目( )可能发生的突发性事件或事故，引起有毒有害和易燃易爆等物质泄漏，所造成的人身安全与环境影响和损害程度，提出合理可行的防范、应急与减缓措施，以使建设项目事故率、损失和环境影响达到可接受水平。

A．建设期间

B．运行期间

C．建设、运行、退役期间

D．建设和运行期间