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问题 问答题

（1）如图甲所示，O是杠杆的支点．请画出力F的力臂，并用字母l表示．

（2）一束光线从空气斜射向水面，请在图乙中画出折射光线的大致方向．

答案

（1）反向延长F，从点O作力F的作用线的垂线，垂线段的长就是力F的力臂L．如图所示：

（2）首题中已经作出法线；再由光从空气斜射入水或玻璃等透明介质中时，折射角小于入射角的规律作出折射光线，折射光线向法线靠近．如下图所示：

阅读理解

My families often go shopping at weekends. My father drives my mother and me to the supermarket. We all like shopping very much. We always buy some fruits and vegetables. At first, we go to buy some fruits. There are many kinds of fruits. My father likes bananas. We buy some bananas for him. My mother likes apples because she says apples can make her more beautiful.

We buy some red apples for her. I like pears. But today pears are sold out(售完,卖完), so I have to choose another kind of fruit. Oranges look good, and I buy some oranges. And next, we go to buy vegetables are fresh. We buy some broccoli, tomatoes and carrots. I don’t like carrots, but my parents say they are good for my eyes. After shopping, it’s me for lunch. We have lunch nearby. And then we go back home.

一、根据短文内容填空（每空一词).

My father drives my mother and me to the supermarket. We buy some 小题1:      for my father, some 小题2:    for my mother. We want to buy some pears for me, but they are sold out, so we buy some 小题3:     for me. And then we buy some broccoli, tomatoes and 小题4:      . 小题5:     we go back home, we have lunch near the supermarket.

二、在文章中找出下面的英语词组。

小题6:看上去很好                  小题7:首先,一开始                    

三、把文章中的划线句子分别翻译成汉语。

小题8:                                               

小题9:                                               

小题10:                                             .
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填空题

等腰直角三角形的面积是8平方厘米，用8个这样的三角形组成一个正方形，它的周长是______厘米．
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