Sometimes,you just can’t help it.Maybe you’re watching a sad movie,or thinking about the friend who moved away.Next thing you know,you feel pressure in your throat,your eyes are watering,and you have tears running down your cheeks.

　　According to Ad Vingerhoets,a professor of psychology at Tilburg University,in the Netherlands,who is one of the few scientists in the world who have studied crying,there are three types of tears.Basal tears are the first type.They act as a protective barrier between the eye and the rest of the world.Next are reflex tears.They wash your eyes clean when something gets in them.Finally,there are emotional tears.“These are released in response to emotional states,” explains Vingerhoets.

　　Scientists believe crying has something to do with how humans develop and learn to depend on each other.“Humans are very complex social creatures,” says Lauren Bylsma,a professor at the University of Pittsburgh,in Pennsylvania.“It seems that tears serve to arouse help and support from others,” she says.

　　Vingerhoets agrees.“I think that the reason why humans shed tears(流眼泪)has something to do with our childhood,”he says.“That’s the time when we are still dependent on adults for love and protection and care.The major advantage of emotional tears is that you can target them at a specific person.”Vingerhoets says this ability could have come in handy in prehistoric times,when humans were living among dangerous animals.Tears were a safer way to get attention.“In this case,it is better to use a silent signal to ask for help,”he says.

　　Vingerhoets and Byhma do frequent studies to better understand why humans cry.According to Byhma,there is still much more to be discovered.

　　【语篇导读】文章从科学的角度分析了泪水的种类及原因等内容。

　　1.In the scientists’ opinion,crying is 　　　.

　　A.a sign of human evolution

　　B.a result of human kindness

　　C.a cause of personal growth

　　D.a means of relying on each other

　　答案　D

　　解析　细节理解题。根据第三段中的“Scientists believe crying has something to do with how humans develop and learn to depend on each other.”可知,科学家们认为哭和人类如何发展以及如何彼此依靠有关系,所以哭是人们互相依靠的一种方式。

　　2.The underlined phrase “this ability” in the fourth paragraph refers to the ability to 　　　.

　　A.seek help wisely

　　B.aim tears at someone

　　C.cry emotionally

　　D.appeal to other people

　　答案　B

　　解析　词义猜测题。根据第四段中的“The major advantage of emotional tears is that you can target them at a specific person.”可知,Vingerhoets认为泪水的主要优势就是你可以向某一个特定的人流泪。由此可知,this ability指将泪水指向一个特定的目标的能力,故B选项正确。

　　3.From the text,we learn that Ad Vingerhoets and Lauren Bylsma 　　　.

　　A.hold different opinions about the cause of tears

　　B.think positively of the effects of tears

　　C.are working together to study tears

　　D.have learned enough about tears

　　答案　B

　　解析　推理判断题。根据第三段的“It seems that tears serve to arouse help and support from others” 以及第四段中的“Vingerhoets agrees”可知,Lauren Bylsma和Vingerhoets都认为泪水可以帮助寻求别人的帮助和支持。由此可知,他们都认可泪水的积极作用,所以选B项。

　　4.What can be a suitable title for the text?

　　A.The types of tears.

　　B.The components of tears.

　　C.The science of tears.

　　D.The opinions about tears.

　　答案　C

　　解析　主旨大意题。文章从科学的角度,分析了泪水的种类及原因等内容,所以C项适合作该文标题。