While I will explain a bit about the science of stress and relaxation a little later simple way to think about it is that our body 's stress response works like a car alarm. Keep us safe by warning us of the presence of danger in our immediate environment.

But instead of warning us with a loud and annoying sound，our body alarm system lets us know that something is wrong by creating changes in our neurochemistry (神经化学）.If you've ever expe?rienced pain in your stomach，periods of extreme anger, inability to focus or even insomnia (失眠），chances are your body was paying the price in those moments for the brain chemistry of stress.

So if it's so uncomfortable，why not just get rid of stress altogether?

This is not only impractical，it would be dangerous. Let's go back to the metaphor (比喻说法）of the car alarm. If the alarm is turned off altogether，the car is exposed to continual danger without there being any way of your knowing about it until it is too late. It would be like walking through the jungle without any fear signal in the presence of a poisonous snake or other dangerous animals — while it might feel “nice” to be so relaxed，your body actually needs the stress response not only to remind you of danger but also to offer extra adrenaline (肾上腺素) for your heart and extra blood  and oxygen for your arms and legs.

However，if the car alarm goes off at any time，someone just looks at the car with a bit of an attitude，and it becomes equally useless. Not only do we stop paying attention to it，but it begins to drive us and everyone around us becomes a little bit crazy. In the case of our bodies，walking around in a constant state of alarm also has some pretty alarming health consequences，which we will explore in greater depth in the next chapter.

【1】Our body's stress response is compared to a car alarm in that     .

A. they work all the time          B. they both give a signal

C. they work in the same  way      D. they both produce a sound

【2】When our body alarm system works，      .

A. we feel calm

B. we feel excited

B. some changes happen in our brain

D. some changes happen in our heart

【3】What would happen if stress were got rid of completely?

A. We'11 be free of worries.

B. We'11 achieve a sense of safety.

C. We'11 reach a perfect state of mind.

D. We'11 fail to realize the possible danger.

【4】 What's the purpose of giving the example of walking through the Jungle in Paragraph 4?

A. To show the harm of stress.

B. To show the effect of stress.

C. To explain the function of stress response.

D. To explain the necessity of stress response.

答案

【1】B

【2】C

【3】D

【4】D

解析

试题分析：文章用比喻的方法,把人类身体比作车,人类身体劳累也会象车一样报警。

【1】B 细节理解题。在文章中的第一段Keep us safe by warning us of the presence of danger in our immediate environment.通过提醒预警,提醒我们危险的出现。由此句可知，两者的共同点在于，给出预警信号,因此选B。

【2】 C  推理判断题。根据文章第二段最后一句If you've ever expe?rienced pain in your stomach，periods of extreme anger, inability to focus or even insomnia (失眠），chances are your body was paying the price in those moments for the brain chemistry of stress.如果你感觉到胃部疼痛，一段时期的极其愤怒，难以集中注意力，或者失眠，那么你的身体就是在为大脑化学的压力付出代价。由此句可知，身体报警系统工作时，身体是有变化的，如胃部疼痛，极其愤怒， 失眠等。因此C 为正确选项。

【3】 D 细节理解题。从第四段 If the alarm is turned off altogether，the car is exposed to continual danger without there being any way of your knowing about it until it is too late. 可知,如果发动机的报警系统被关掉,车辆就完全暴露在不断的危险中,而没有任何迹象让你知道, 直到太晚。 也就是D 选项的说法，我们不能意识到可能存在的危险。

【4】 D 推理判断题。文章第四段末while it might feel “nice” to be so relaxed, your body actually needs the stress response not only to remind you of danger but also to offer extra adrenaline for your heart and extra blood and oxygen for your arms and legs.句意,就象放松的时候感觉很好一样,你的身体真的需要压力反应,不仅为为了提醒你危险的存在, 也是为了给你的心脏提供肾上腺,为你的胳膊,腿提供额外的血液和氧气。由此可知，如果完全失去压力， 我们就不能意识到潜在危险的存在，就象人走在丛林中而不知毒蛇,猛兽的存在,这样 很容易引起读者共鸣, 以此来说明压力反映存在的必要性, 所以选D。