Most of us think that when we step under a shower we’re getting clean．We are, but we’re also giving a home to lots of tiny little creatures we didn’t even know about．
A showerhead carries thousands of bacteria (細菌) called Mycobacterium．These can cause problems like coughs and tiredness, and a general feeling of poorliness (身體不舒服)．When you turn on the water, the bacteria go from the showerhead onto and into your body．
This is a finding of Norman R．Pace and his team at the University of Colorado, in the US．The scientists investigated bacteria in all kinds of human environment, including showers．
Pace's team looked at 45 showerheads in nine American cities．They discovered that 30 percent of them had large amounts of flying Mycobacterium．
But Pace said that they pose few threats to the health．Only those with a frail (脆弱的) immune (免疫的) system might need to worry．
He told the New York Times that the bactertia are not as unpleasant as might be thought．He said that having a shower is no more dangerous than anything else we do in the morning．
But for those who feel sick about the idea of all those microorganisms (微生物), he had some advice．
Let the water run for 30 seconds before getting into the shower．Why? The number of bacteria is smaller than when the water is just turned on．If that seems like a waste of water, he added that you could also change your showerhead every few months．
But Pace had good news too．He has also been testing the air in US subways．Apart from iron particles (粒子), which are ground off the track by the wheels of trains, subway air is fresh．The reason is that a train’s movement pumps fresh outdoor air into the tunnels(隧道)．
Pace explained that he wanted to understand the natural microbial(微生物的) environments of public places．This kind of knowledge might help detect the microbes to be used in a bioterrorist (生物恐怖分子) attack．
49．According to the finding of Norman R．Pace, after taking a shower, we might ______．
A．get much dirtier                B．be covered by bacteria
C．get a frail immune system      D．catch a cough or feel tired
50．Pace’s research into showers shows that ______．
A．there is no reason to fear microorganism
B．shower water contains much less bacteria after being left to run for 30 second
C．having a shower in the morning is more dangerous than at other time
D．of 45 showerheads surveyed in nine cities, 30 carried large amounts of Mycobacterium
51．According to the research of Pace’s team, which of the following contributes to fresh air in US subways?
A．Train wheels．               B．Iron particles．
C．The movement of the trains． D．Air conditioners on the trains．
52．The word “detect” in the last paragraph probably means “______”．
A．to discover      B．to protect        C．to make   D．to prevent

49---52    DBCA  

49．D考查細節(jié)理解。第二段說，淋浴的噴頭上有數(shù)以千計的細菌，使用者會引起咳嗽、疲勞、身體不舒服的癥狀。
50．B考查細節(jié)理解。從第八段可知B項陳述正確。
51．C考查細節(jié)理解。第九段說，他們的研究發(fā)現(xiàn)，地鐵列車的來回移動將外面的空氣抽到隧道里，因此地鐵的空氣很新鮮。
52．A考查猜測詞義。從語境看，劃線詞表示了解公共場合的自然微生物環(huán)境，了解這方面的知識能幫助我們“監(jiān)測/發(fā)現(xiàn)”恐怖分子的生物攻擊所使用的微生物。
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科目：高中英語 來源：不詳 題型：閱讀理解

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科目：高中英語 來源：不詳 題型：閱讀理解


D
Everyone knows you must exercise regularly to keep good health. Indeed, staying physically fit is a big part of our culture. we consider（or rightly so）that healthy people are attractive people. Since most of us want to be attractive, there is no shortage of exercise clubs, training videos, magazines and books offering to help us stay physically fit.
Unfortunately, however, our culture doesn’t place the same emphasis on mental fitness. Although we tend to like men and women with strong, healthy-looking bodies, we don’t have the same degree of respect or attraction for smart, educated, mentally healthy people. This is a pity, because there are great rewards for people who have developed the ability to think well.
If your mind is well trained and flexible, you will be able to understand a great deal of what happens around you. And if you are also well educated --- that is, if you understand basic science, mathematics, music, art, literature, history and so on --- you will find it much easier to make good decisions throughout your life. Over the long run, this leads to a sense of control over your destiny and a much better life than otherwise.
People who are poorly educated or who don’t think well --- that is, people who are not mentally fit --- see things differently. Their world is controlled by mysterious, often malevolent（惡意的）forces. Such people live within a system they will never master, forced to follow rules they will never understand. Although it may not be obvious, most spend their lives being manipulated（控制）by others. They are told what to do, what to think, how to spend their money, and what they should and should not aspire（渴望）to in life.
In my opinion, if you want to live well, you must be able to use your mind well. For this reason, I want you to be able to concentrate, to solve problems, to understand complex ideas, and to think clearly and quickly. Such skills will make it easier for you to make informed decisions, understand current events, choose good friends, manage your money well, make wise lone-term decisions and appreciate music, art and literature.
The key to developing such skills is to enjoy learning, and to have the ability and motivation to teach yourself.
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A. too little has been done to help people to keep physically fit
B. too much has been done to help people to keep physically fit
C. mentally healthy people are not as popular as physically healthy people
D. physically healthy people are not as popular as mentally healthy people
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A. the understanding of a great deal of what goes on around you
B. the understanding of basic science and mathematics
C. good training in body and mind
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