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<B>第四讲　课后习题讲解<p></p></B></P>
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课后习题讲解：<p></p></P>
练习1<p></p></P>
thus however meanwhile likewise accordingly furthermore then therefore otherwise moreover besides then hence also consequently<p></p></P>
1) Roan moved to New York; however, her mother stayed in Boston.<p></p></P>
2) You have disregarded my advice; therefore, I will not help you again.<p></p></P>
3) The leaders settled the argument; otherwise, there would have been war.<p></p></P>
4) Harrison is kind; moreover, he is generous.<p></p></P>
5) Mr. Carr was an invalid all his life; nevertheless, he had an active career.<p></p></P>
6) Television is entertaining; furthermore, it is sometimes instructive.<p></p></P>
7) We must meet the deadline; hence, a decision is needed now<p></p></P>
8) I will study medicine for six years; then I will be a doctor.<p></p></P>
9) I live too far away to visit you often; besides, you are never home.<p></p></P>
10) He requested an opportunity to make up the work he had missed; accordingly, his teacher gave him special help.<p></p></P>
11) The road was wet and slippery; consequently, there were many accidents.<p></p></P>
12) All of Mrs. Jackson’s ancestors were active and long-lived; likewise, she is very healthy at age 75.<p></p></P>
13) I held the dog; meanwhile, my fried washed it.<p></p></P>
14) He put out the fire quickly; thus, a great disaster was avoided.<p></p></P>
练习2<p></p></P>
1) He looked at her and was surprised. → He looked at her in surprise.<p></p></P>
2) The meeting ended and everyone felt bitter. → The meeting ended in bitterness.<p></p></P>
3) She had died and he was grieved. → He was in grief over her death.<p></p></P>
4) We were greeted by young men who wore black uniforms. → We were… in black uniforms.<p></p></P>
5) He refused to talk to them. So he had aroused suspicion. → He had aroused…by refusing to…<p></p></P>
6) She smoked a lot and her fingers were brown with nicotine. → She …, her fingers brown…<p></p></P>
7) The little fellow looked around. His hands were in his pockets. → The little…, his hands in…<p></p></P>
8) The traitor’s face was beaming with smile and he pocketed the wad of banknotes and he was not aware of the risk he was taking. → His face beaming with smile, the traitor pocketed the wad of banknotes, unaware of …<p></p></P>
9) She had been confined to bed for a long time. This had impaired the function of her ankles.<p></p></P>
→ Long confinement to bed had impaired the function of her ankles.<p></p></P>
10) If you study Mars carefully through a telescope, you will se a number of dark, blue-green markings. → A carefully study of Mars through a telescope will reveal a number of dark, blue-green markings.<p></p></P>
练习3<p></p></P>
Illustration for example a case in point an example for instance such as<p></p></P>
What Is Language?<p></p></P>
A language is a signaling system which operates with symbolic vocal sounds, and which is used by a group of people for the purposes of communication.<p></p></P>
Let us look at this definition in more detail because it is language, more than anything else, that distinguishes man from the rest of the animal world.<p></p></P>
Other animals, it is true, communicate with one another by means of cries: for example, many birds utter warning calls at the approach of danger; apes utter different cries, such as expressions of anger, fear and pleasure. But these various means of communication differ in important ways from human language. For instance, animals’ cries are not articulate. This means, basically, that they lack structure. They lack, for example, the kind of structure given by the contrast between vowels and consonants. They also lack the kind of structure that enables us to divide a human utterance into words.<p></p></P>
We can change an utterance by replacing one word in it by another: a good illustration of this is a soldier who can say, “tanks approaching from the north”, or he can change one word and say “aircraft approaching from the north” or “tanks approaching from the west”; but a bird has a single alarm cry, which means “danger!”<p></p></P>
This is why the number of signals that an animal can make is very limited: the famous gorilla, the Great Tit is a case in point; it has about twenty different calls, whereas in human language the number of possible utterances is infinite. It also explains why animal cries are very general in meaning.<p></p></P>
4. 描述法<p></p></P>
1) 时间顺序<p></p></P>
To get the most out of his textbooks, a student should follow several steps very carefully. First, he should make a preliminary survey of each book to get a general idea of what the book contains. Second, he should read for deeper understanding and formulate questions as he reads. Next, he should make notes of the major points of each chapter. After that he should test himself to be sure that he can answer questions likely to be raised in class and in examinations. Finally, he should review his notes and reread any parts of the book that are unclear to him.<p></p></P>
常用的连接词：<p></p></P>
起始: first, firstly, at first, first of all, in the first place, to begin with<p></p></P>
中间: second, secondly, in the second place, next, afterwards, after that, then, later, another, third, thirdly, still another, in addition, besides, furthermore<p></p></P>
最后: lastly, at last, finally, eventually, in the end<p></p></P>
2) 空间顺序<p></p></P>
A. My classmate Joe is easy to locate in a crowd of people. He has a thin, oblong face. Under his light brown hair, which is thick and straight, his forehead is smooth, tanned, and slightly sunburned. His heavy eyebrows are darker than his hair. His eyes are a pale sky-blue, fringed with short brown eyelashes. One eye looks a little smaller than the other. His long, straight nose is sunburned. There is a noticeable scar on his upper lip just under his nose. He has a clear-shaven chin. His mouth is fairly wide, but his lips are thin, and they smile lightly, even in sleep.<p></p></P>
常用衔接词和短语：be situated/located at, be surrounded by, next to, to the east/west of, close to, from…to…, over, under, below, between, across, from, opposite, adjacent, far behind, at the top, here, straight ahead, at the right, in the center, in the distance, beyond, far behind, nearby<p></p></P>
5. 因果法<p></p></P>
1) With coming of the industrial age and the great increase in world population, our ability to pollute the air began to overtake nature’ s ability to purify it. Consequently, the effects were first felt in areas of heavy industry. As a result, people in those areas suffered from lung and heart ailments. Since then, the problem has not only increased but has also spread throughout the world. For these reasons, it is important to give attention to controlling air pollution.<p></p></P>
2) Work is an important part of one’s life. We can derive some pleasure and satisfaction from the completion of work. When we see the result of our work, we will feel happy. On the other hand a society would not keep going if people didn’t work and didn’t produce wealth. We need to work and we need to get a pay, with which we can support ourselves and our family as well.<p></p></P>
常用动词和动词短语：cause, lead to, give rise to, result in, bring about, be due to, be caused by, result from, be the result of, be the effect of, accordingly<p></p></P>
课堂练习：运用学到的展开方法分析下面三篇短文。<p></p></P>
1) Food and Our Weight<p></p></P>
Food is the source of energy for the body. Food and the energy it produces are important. Indeed, we need this energy just to keep alive. Naturally, energy is required just to digest the food needed to produce energy in the first place. Moreover, energy is essential for all continuous body processes such as breathing, the beating of the heart, and the maintenance of muscle and bone. Also, children and youth need energy for growth. In brief, we need the energy produced by food for carrying out all work and leisure activities.<p></p></P>
However, when the food we eat provide more energy than is needed to meet the demands of the body, the extra energy is stored as fat. As a result, we gain weight if we furnish the body regularly with too much food. On the other hand, the body uses stored fat if the foods we eat provide less energy than is needed. Accordingly, the body loses weight. Thus, if all fatty tissue are used up, the body uses its other tissues for energy, thereby producing an unhealthy and dangerous condition. For these reasons, it is important to understand the relationship between the food we eat and our body weight.<p></p></P>
2) Agricultural Development<p></p></P>
To increase agricultural production is difficult and complicated. Indeed, many different conditions have to be created or changed, involving many people and governments. Of course, this is difficult. In a like manner, it is very complicated. In spite of its great contributions to all kinds of development, technology alone is not sufficient. Equally important are good judgment, imagination, experimentation, and good hard work. It goes without saying that agricultural development requires the cooperation of people as well as the resources provided by nature.<p></p></P>
These difficulties notwithstanding, agricultural development is taking place. For example, agricultural workers experiment with crops. Furthermore, researchers create new kinds of crops. Also, they discover improvements in fertilizers and irrigation. Moreover, agricultural engineers develop new kinds of equipment. In addition, marketing experts find improved ways of purchasing and marketing agricultural products. Likewise, transportation experts develop better ways of moving agricultural products to the markets. Finally, government officials appropriate funds to assist financially in the development of agricultural production. Briefly stated, these are only a few of the ways to promote agricultural development.<p></p></P>
3) There is one point that I wish to explain to readers. No matter whether a marriage is between people of the same or different nationalities, communication between husband and wife requires a good match of educational backgrounds. With this kind of base, conflicts can be settled more easily. My wife has a degree from a university in the US, and I find that this makes it easier for us to come to agreement on social and family problems. If she had not received such an education and as a result did not understand me when I speak of the Internet, democracy and so on, how could we communicate?<p></p></P>
练习 5<p></p></P>
1) The Importance of libraries (列举法)<p></p></P>
2) The reasons for no homework to the college students at the weekend (因果法、举例法)<p></p></P>
3) Nowadays, the computer has found wide applications in many areas. (举例法)<p></p></P>
4) The Significance of Work （因果法、举列法）<p></p></P>