题目内容
In certain occupations colour blindness can be dangerous and candidates are tested most carefully. For example, when fighting at night, soldiers use lights of flares to signal to each other. A green light may mean "Advance" and a red hght may mean "Danger! Keep back!" You can see what will happen if somebody thinks that red is green! Colour blindness in human' beings is a strange thing to explain. In a single eye there are millions of very small things called "cones". These help to see in a bright light and to tell the difference between colours. There are also millions of "rods" but these are used for seeing when it is nearly dark. They show us shape but not colour. Wait until it is dark tonight, then go outside. Look round you and try to see what colors you can recognize.
Birds and animals which hunt at night have eyes which contain few or no cones at all, so they cannot see colours. As far as we know, bats and adult owls cannot see colours at all. Similarly cats and dogs cannot see colours as well as we can. Insects can see ultraviolet rays which are invisible to us, and some of them can even see X-rays. The wings of a moth may seem grey and dull to us, but to insects they may appear beautiful, showing colours which we cannot see. Scientists know that there are other colours around us which insects can see but which we cannot see. Some insects have favorite colours. Mosquitoes like blue, but do not like yellow. A red light will not attract insects but a blue tamp will.
Among people who suffer from colour blindness ______.
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The men who【C6】______the machines of the Industrial Revolution【C7】______from many backgrounds and many occupations. Many of them were【C8】______inventors than scientists. A man who is a【C9】______scientist is primarily interested in doing his research【C10】______. He is not necessarily working【C11】______that his findings can be used.
An inventor or one interested in applied science is【C12】______trying to make something that has a concrete【C13】______. He may try to solve a problem by using the theories【C14】______science or by experimenting through trial and error. Regardless of his method, he is working to obtain a【C15】______result: the construction of a harvesting machine, the burning of a light bulb, or one of【C16】______other objectives.
Most of the people who【C17】______the machines of the Industrial Revolution were inventors, not trained scientists. A few were both scientists and inventors. Even those who had【C18】______or no training in science might not have made their inventions【C19】______a groundwork had not been laid by scientists years【C20】______.
【C1】
听力原文：W: What time will the film start？
M: It's planned to begin at 9 o'clock, and now it's 8:45.
How long will they wait until the film starts ？
Part A
Directions: You will hear 10 short dialogues. For each dialogue, there is one question and four possible answers. Choose the correct answer ― A, B, C or D, and mark it in your test booklet. You will have 15 seconds to answer the question and you will hear each dialogue ONLY ONCE.
听力原文：W: The car has broken down again and it refused to move.
M: We'll have to call Mr. Smith right away.
What job does Mr. Smith probably have？
Part A
Directions: Read the following three texts. Answer the questions on each text by choosing A, B, C or D. Mark your answers on ANSWER SHEET 1.
In the past, it was believed that depression was more prevalent among the poorer and less educated people, but that is not the case. The truth is, depression can afflict people from all walks of life, and often it hits the most ambitious, creative and conscientious, it is fallacious to think that people on the corporate rung of the social ladder are not prone (易于……) to this malady (疾病). In fact, executives and professionals who are burdened with mounting pressures in their work may succumb to all these pressures and become depressed. The suicide of Vincent Foster, Jr., a noted American lawyer and White House official is a case in point. Despite the glamour of his position, which many people thought enviable, he felt overburdened with pressures and decided to take the easy way out.
Studies show that people born later in this century have experienced much more depression than those born earlier. In fact the rate of depression over the last two generations has increased tenfold. Experts theorize that it could be due to the fact that the younger generations have higher expectations from life and are therefore more likely to suffer from failure disappointment and hence, depression.
Depression is easily recognizable. The depressed person feels sad or down in the dumps, and loses interest in even the most pleasurable activities. Moreover, he suffers from either significant gain or loss of weight, sleeplessness or oversleeping, sluggish movement and thinking, fatigue, feelings of guilt and worthlessness, impaired concentration and forgetfulness, and in extreme cases, the afflicted person may have suicidal tendencies. It is often believed that depression runs in the family, but this is not conclusively so, since there are cases where depressed persons do not have a history of depression in their families. Depression is often work related although at times it has its roots in family relations.
People who suffer from depression need not stay in the closet, since it is not a sin or a shame to be depressed. A prompt visit to a psychologist means prompt treatment and hence prompt recovery. Experts guarantee that depression is easily treatable, and in nip in tile bud cases, the patient fully recovers in a few days, thtmks to the variety of effective treatment available.
According to the author, depression ______.
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