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哈工大 有限元理论ppt课件.ppt

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1、B. 436-5990 C. 436-4112 D. 436-410857. If you cant find any printer paper in the computer room, which number should you dial? A.436-4119B. 436-5990 C. 436-4112 D. 436-410858. You should go to room _ when youre giving a birthday party for 11 people. A. BO77B. 323 C. 221 D. 11959. How would you make t

2、he call when you want to call a friend at 738-9087 while staying in Room 188? A. Press 9, then 738-9087.B. Dial 9 first, then 8908. C. Press 89087.D. Ring 9087.60. Which of the following statements is true? A. You can call the housing office after 9 p.m. B. Your personal things will be well kept in

3、the common room. C. You can call 436-4119 to reserve the meeting room. D. Each room is equipped with a television.CThe monarch is one of the most beautiful butterflies. It is famous for its yearly migration(迁徙)from the northern part of North America to Mexico, There, millions of monarchs spend the w

4、inter packed closely together in one small area. This migration is one of the greatest wonders of nature. Yet this behavior has now put the monarch at risk.Every September, millions of monarchs from the United States fly to Mexico. After about two months of flying time, they reach their sanctuary(庇护

5、所)in central Mexico. Then, in the warm climate of private and quiet valleys, far from most human activity, the butterflies create one of natures great scenes. They cover every tree with bright color. The show lasts until spring, when the butterflies return north.While they are all crowded together,

6、the monarchs are highly weak. If the environment in those valleys was disturbed, the whole species could be hurt or even wiped out. That is why for many years scientists who knew about the monarchs winter sanctuary kept the location a secret.In recent years, however, the monarchs secret has been rev

7、ealed. Today, the butterflies winter sanctuary is crowded with tourists, who disturb the environment. Worse still, local farmers who need more land to farm have begun to take up the area. They are cutting down trees, making it difficult for the butterflies to survive. They should not farm in the mon

8、archs sanctuary.Concerned people should act immediately to protect the species winter sanctuary. Local farmers must be aided so that they no longer need to take land from the butterflies. Tourist visits to the butterflies hidden valleys must also be limited. Unless these steps are taken soon, in a f

9、ew years the monarch butterfly of North America may be just a beautiful memory.61.What do we know about monarch butterflies?A. They fly to the US in autumn. B. They spend the winter in a pack.C. They are the most beautiful butterflies. D. They have been known to human beings until recent years.62. What is Paragraph 2 mainly about? A. The monarchs diet. B. The monarchs f翺抨欀瀀栀琀洀氀圀柀曂

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