问题 多项选择题

电流的热效应、化学效应、机械效应对人体的伤害有电烧伤、电烙印、皮肤金属化等多种。下列关于电流伤害的说法中,正确的有()。

A.不到1OA的电流也可能造成灼伤

B.电弧烧伤也可能发生在低压系统

C.短路时开启式熔断器熔断,炽热的金属微粒飞溅出来不至于造成灼伤

D.电光性眼炎表现为角膜炎、结膜炎

E.电流作用于人体使肌肉非自主地剧烈收缩可能产生伤害

答案

参考答案:A, B, D, E

解析:电流灼伤是指人体与带电体接触,电流通过人体时,因电能转换成的热能引起的伤害。电流灼伤一般发生在低压电气设备上,数百毫安的电流即可造成灼伤,数安的电流则会形成严重的灼伤。电弧烧伤指由弧光放电造成的烧伤,是最严重的电伤。电弧烧伤既可以发生在高压系统,也可以发生在低压系统。在低压系统中,当线路发生短路,开启式熔断器熔断时,炽热的金属微粒飞溅出来会造成灼伤;电流作用于人体,使肌肉产生非自主的剧烈收缩可能产生伤害;电光性眼炎其表现为角膜和结膜发炎。

阅读理解

In our life, we have rarely expressed our gratitude to the one who lived those years with us. In fact, we don't have to wait for anniversaries to thank the ones closest to us and the ones so easily overlooked. If I have learned anything about giving thanks, it is this: give it now! While your feeling of appreciation is alive and sincere, act on it. Saying thanks is such an easy way to add to the world's happiness.

Saying thanks not only brightens someone else's world, it brightens yours. If you're feeling left out, unloved or unappreciated, try reaching out to others. It may be just the medicine you need. Of course, there are times when you can't express gratitude immediately. In that case, don't let embarrassment sink you into silence and speak up the first time you have the chance.

Once a young minister, Mark Brian, was sent to a remote parish(教区)of Kwakiutl Indians in British Columbia. The Indians, he had been told, did not have a word for thank you. But Brian soon found that these people had unusual generosity. Instead of saying thanks, it is their custom to return every favor with a favor of their own, and every kindness with an equal or superior kindness. They do their thanks. I wonder if we had no words in our vocabulary for thank you, would we do a better job of communicating our gratitude? Would we be more responsive, more sensitive, more caring?

Thankfulness sets in motion a chain reaction that transforms people all around us-including ourselves. For no one ever misunderstands the melody(旋律)of a grateful heart. Its message is universal; its poems transcend(超越)all earthly barriers; its music touches the heaven.

小题1:Who do we easily forget to express our thanks to according to the writer?

A.Friends not meeting for a long time.

B.Former teachers and friends.

C.People we want to get close to.

D.Our family members and good friends.小题2: When we say something for what others do for us, it ______.

A.benefits the people who do something for us

B.is good for both us and people who help us

C.wastes our and our friends' time at the same time

D.does harm to both us and people who help us小题3:What does the writer mean in the third paragraph?

A.The only way to thank others is to express by your own words.

B.The best way to thank others is to do something for them.

C.We can thank people who help us in various ways.

D.We can thank people who help us in two ways.小题4:The way to make us feel happy is ______ when we think we ourselves are forgotten in the world.

A.to help and appreciate others

B.to ask others to help us

C.to remind others of our helping them

D.to ask someone to help others

单项选择题