问题
填空题
如图所示的甲、乙两棵树，它们根系的深浅及发达程度基本相同，______树容易被吹倒或折断．把风对它的吹力看做动力，因为______．
答案
可以把树看作一个杠杆，支点为树根处，阻力和阻力臂一定，当都受到同样大小的风力作用时，树越高，其力臂越大，由杠杆的平衡条件F1l1=F2l2，可知乙树容易被风吹倒或吹折．
故答案为：乙；乙的动力臂大．
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如图所示的甲、乙两棵树，它们根系的深浅及发达程度基本相同，______树容易被吹倒或折断．把风对它的吹力看做动力，因为______．
可以把树看作一个杠杆，支点为树根处，阻力和阻力臂一定，当都受到同样大小的风力作用时，树越高，其力臂越大，由杠杆的平衡条件F1l1=F2l2，可知乙树容易被风吹倒或吹折．
故答案为：乙；乙的动力臂大．
I was in a strange city and I didn't know the city at all, and what is more, I could not speak a word of the language. After having spent my first day in the town-centre, I decided to lose my way on my second day, since I believed that this was the simplest way of getting to know the strange city. I got on the first bus that passed, rode on it for several stops, then got off it and walked on. The first two hours passed pleasantly enough. Then I decided to turn back to my hotel for lunch. After walking about for some time, I decided I had better ask the way. The trouble was that the only word I knew of the language was the name of the street in which I lived and even then I pronounced it badly. I stopped to ask a friendly-looking newspaper-seller. He smiled and handed me a paper. I shook my head and repeated the name of the street and he put the paper into my hands. I had to give him some money and went on my way. The next person I asked was a policeman. The policeman listened to me carefully, smiled and gently took me by the arm. There was a strange look in his eyes as he pointed left and right and left again. I thanked him politely and began walking in the direction he pointed. About an hour passed and I noticed that the houses were getting fewer and fewer and green fields were appearing on either side of me. I had come all the way into the countryside. The only thing left for me to do was to find the nearest railway station. 小题1:The writer believed that if you wanted to get to know a strange city, ______.
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