Many people believe the glare from snow causes snowblindnenss. Yet, 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 foucs on in a broad expanse of barren snow-covered terrain. So his gaze continually shifts and jumps back and forth over the entire landscape in search of tsomething to look at. Finding nothing, hour after hour, the eyes never sotp searching and the eyeballs become sore and the eye muscles ache. Nature offsets this irritation by producing more and fluid which covers the eyeball. The fluid coversthe eyeball in increasing quantity until vision blurs, then is obsured,and the result is total, even though temporary,snowblindness.
Experiments led the Army to a simple method of overcoming this problem. Scouts ahead of a main body of 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 too can focus . The men following can then see something.Their gaze is arrested. Their eyes focus on a bush and having found something to see,stop scouring the snow-blanketed lanscape. 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 solid white terrain is overcome.
1.To prevent headaches, watering eyes and blindness caused by the glare from snow, dark glasses are_____.
a.indispensible b.useful c.ineffective d.available
2.When the eyes are sore tears are produced to ________.
a.clear the vision b.remedy snowblindness c.ease the irritation d.loosen the muscles
3.Snowblindness may be avoided by_______.
a.concentrating to the solid white terrain
b.searching for something to look at in snow-covered terrain
c.providing the eyes with something to foucs on
d.covering the eyeballs with fluid
4.The scouts shake snow from evergreen bushes in order to _______.
a.bive the men behind something to see
b.beautify the landscape
c.warm themselves in the cold
d.prevent the men behind from losing their way
5.A suitable title for this passage would be _______.
a.snowblindness and how to overcome it
b.natrue's cure for snowblindness
c.soldiers in the snow
d.snow vision
答案:CCCAA
Newdays,a standard for measuring power has changed.These changes foretell a new standard for measuring power.No longer will a nation's political influence be based solely on the strength of its military forces. Of course, military effectiveness will remain a primary primary measure of power.But political influence is also closely tied to industrial competitiveness. It's often said that without its military the Soviet Union would really be a third-world nation. The new standard of opwer and influence that is evolving now places more emphasis on the ability of a country to compete effectively in the economic markets of the world.
America must recognize this new course of events. Our success in shaping world events over the past 40 years has been the direct result of our ability to adapt technology and to take advantage of the capabilities of our people for the purpose of maintaining peace. Our industrial prowess over most of this period was unchallenged. It is ironic that it is just this prowess that has enabled other countries to prosper and in turn to threaten our industrial leadership.
The competitiveness of America's industrial base is an issue bigger than the Department of Defense and is going to require the efforts of the major institutional forces in our society-government,industry,and education. That is not to say that the Defense Department will not be a strong force in the process because we will. But we simply cannot be, nor should we be, looked upon by others as the savior of American industry.
1. Now a nation's political influence depends on _________.
a. the strength of its military forces b. its ability to compete in industry
c. economic markets d. both a and b
2. The Soviet Union was not listed as a third-world nation just because of _________.
a. its powerful military forces b. its vast land
c. its industrial competitiveness d. its contributions to world peace
3. The author indicates that ______ is threatening American political power.
a. other countries b. the declining U.S. industrial base
c. a new standard for measuring power d. less advanced technology
4. America succeeded in shaping world events over past 40 years probably because of ___________.
a. its ability to adapt technology
b. its ability to take advantage of the capabilities of its people
c. its ability to compete in the world markets
d. both a and b
5. The purpose of writing this article is __________.
a. to draw the readers' attention to a new standard for measuring power
b. to demonstrate American political influence in the world
c. to emphasize that efforts must be made to strengthen the declining U.S. industrial base
d. to show American industrial prowess
答案:dabdc
Social customs and ways of behaving change. Things which were considered impolite many years ago are now acceptable. Just a few years ago, it was considered impolite behaviour for a man to smoke on street. No man who thought of himself by smoking when a lady was in a room.
Customs also differ from country to country. Does a man walk on the left or the right of a woman in your country? Or doesn't it matter? Should you use both hands when you are eating? Should leave one in your lap,or on the table?
The Americans and the British not only speak the same language but also share a large number of social customs. For example, in both America and England people shake hands when they meet each other for the first time. Also, most Englishmen will open a door for a wonman or offer their seat to a woman , and so will most Americans. Promptness is important both in England and in America. That is , if a dinner invitation is for 7 o'clock , the dinner guest either arrives close to that time or calls up to explain his delay.
The important thing to remember about social customs is not to do anything that might make other people feel uncomfortable-----especially if they are your guests. When the food was served , one of the guests strated to eat his peas with a knife . The other guests were amused or shocked , but the host calmly picked up his knife and began eating in the same way. It would have been bad manners to make his guest feel foolish or uncomfortable.
1.If one has accepted a dinner invitation ,what should he do if he is tobe late for the dinner?
a.He should find an excuse b.He should adk for excuse.
c.He should say sorry d.He should telephone to explain his being late.
2."It would have been bad manners to make his guests feel foolish or uncomfortable." "Bad manners " means ________.
a.ugly b.dishonest c.impolite d.shameful
3.which of the following do you think is the best tiltle for this passage?
a.Social Customs and Customs b.Social Life
c.American and British Customs d.Promptness Is Important
4.According to the text, the best host_______.
a.tries his best to make his guests feel comfortable
b.makes his guests feel excited
c.tries to avoid being naughty to his guests
d.tries to avoid being foolish
5.The author of this article may agree with which of the following?
a.The guest who ate his peas with a knife
b.The other guests who were amused or shocked
c.The host who picked up his knife and began eating in the same way
d.None of the above
答案:dcaac
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