Many people believe the glare（炫目的光）from snow causes snowblindness. Yet, with dark glasses or not, they find themselves suffering from headaches and watering eyes, and even snowblindness ,when exposed to several hours of“ snow light”.

　　The United States army has now determined that glare from snow does not cause snowblindness in troops in a snow -covered country. Rather ,a man’s eyes frequently find nothing to focus on （聚集） in a broad space of snow- covered without- grass land. So his gaze continually moves and jumps back and forth over the entire landscape in search of something to look at. Finding something, hour after hour, the eyes never stop searching and the eyeballs become tired and the eye muscles ache. Nature makes up for this discomfort by producing more and more fluid （流 體） which covers the eyeball. The fluid covers the eyeball in increasing quantity until it makes eyes difficult to see dearly, and the result is total, even though for a short time, snowblindness.

　　Experiments led the Army to a simple method of overcoming this problem. Scouts（偵察兵）ahead of the troops are trained to shake snow from evergreen bushes, creating a dotted line as they cross completely snow - covered landscape. Even the scouts themselves throw lightweight, dark - colored objects ahead on which they can focus too. The men following can then see something. Their gaze is arrested. Their eyes focus on a bush and having found something to see, stop searching the snow -blanketed landscape. By focusing their attention on one object at a time. the men can cross the snow without becoming hopelessly snowblind or lost. In this way the problem of crossing a continuous white land is overcome.

To prevent snowblindness caused by the strong light from snow, wearing glasses or not ________.

　　A. depends on whether the snow is white enough

　　B. makes no difference

　　C. makes much difference

　　D. depends on whether the snow is thick

When the eyes are tired, tears flow out ________.

　　A. to clear the vision

　　B. to make the eyes stop searching

　　C. to make the vision unclear

　　D. to produce more and more liquid

Snowblindness can be avoided ________.

　　A. by moving one’s gaze back and forth

　　B. by walking ahead and keeping looking around

　　C. by making up for the discomfort of one’s eyes

　　D. by providing the eyes with something to focus on

【小題1】B

【小題2】C

【小題3】D


解析:

【小題1】第一段提到戴不戴眼鏡都會產(chǎn)生“雪盲”的癥狀，如頭疼，流淚甚至雪盲。

【小題2】　第二段結(jié)尾部分說此時淚水流出來充滿眼眶，眼睛看不清，導(dǎo)致雪盲。

【小題3】第三段提到的偵察兵的做法告訴我們，雪盲的產(chǎn)生是因為在雪地里眼睛找不到具體目標(biāo)，由于尋找不到看的物體才產(chǎn)生雪盲。人們就將灌木上的雪去掉，扔一些深色物體，其目的是D。

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科目：高中英語 來源： 題型：050

　　 I have a rule for travel:Never carry a map.Iprefer to ask for directions.

　　 Foreign visitors are often puzzled in Japan because most streets there don't have name.In Japan,people use landmarks in their directions instead of street names.For example,the Japanese will say to travelers, “Go straight down to the corner. Tun left at the big hotel and go pass a fruit market. The post office is across from the bus stop.”

In the countryside of the American Midwest,usually there are not many landmarks. There are no mountains, so the land is very flat(平坦的). In many places there are no towns or buildings with tell you directions and distance. In Kansas or Iowa, for example, people will say, “Go north two miles. Turn east,and then go another mile.”

　　 People in Los Angeles, California, have no idea of distance on the map: They measure distance by means of time, not miles. “How far away is the post office?” you ask.　　“Oh,” they answer, “It's about five minutes from here.”you say, “It's about five minutes from here.” You say, “Yes, but how many miles away is it?” They don't know.

Peop;e in Greece sometimes do not even try to give directions because visitors seldom understand thi Greek language. Instead of giving you the direction, a Greek will often say, “Follow me.” Then he'll lead you through the streets of the city to the post office.

Sometimes a person doesn't know the answer to your question, What happens in this situation? A New Yorker might say, “Sorry, I have no idea.” But in Yucatan, Mexico, no one answers, “I don't know.” People in Yucatan think that “I don't know” is impolite. They usually give an answer, often a wrong one.A visitor can get very, very lost in Yucatan!

　　 One thing will help you everywhere-in Japan, in the United States in Greece, in Mexico, or in any other place. You might not understand a person's words, but maybe you can understand his body language. He or she will usually turn and then point in the correct direction. Go iin that direction, and you may find the post office!

1.The passage mainly tells us that_______.

A.never carry a map for travel

B.there are not many landmarks in the American Midwest

C.there are different ways to give directions in different parts of the world

D.New Yorkers often say, “I have no idea,” but people in Yucatan, Mexico, never say this

2.In which place do people tell distance by means of time?

A.Japan.

B.American Midwest.

C.Los Angeles,California.

D.Greece

3.In the passage,_______countries are mentioned by the writer.

A.seven　　　　 B.four　　　　C.eight　　　　 D.five

4.Which of the following is wrong?

A.Travelers can learn about people's customs by asking questions about directions.

B.A person's body language can help you understand directions.

C.People in some places give directions in miles, but people in other places give directions by means of time.

D.People in different places always give directions in the same way: They usr street namees.

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