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问题 选择题

函数y=2-x的值域是（　　）

A．R

B．（-∞，0）

C．（-∞，1）

D．（0，+∞）

答案

由y=2-x=(

1
2
)x，知函数的定义域为R，值域为（0，+∞）．

故选D．

填空题

我能用自己的话说出下面诗句的意思。     

1．碧玉妆成一树高，万条垂下绿丝绦。

                                                                                                                      

                                                                                                                       

2．等闲识得东风面，万紫千红总是春。

                                                                                                                       

                                                                                                                        

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补全对话，情景问答
从方框中选取适当的句子，补全对话
A. He likes the computer. He plays computer games sometimes.
B. He's in Junior 1. A big boy now.
C. Can I have a look at the one near the window?
D. Yes, the yellow one with big ears.
E. Nice. Can it sing?
F. No. We have many toy cars at home.
G. Good. I'll take a big one.
H. Good. I'm sure my son will like it. Do you have any big robot?
I. Yes. I'm looking for something for my son.
J. No. We have many planes at home, too.
A: May I help you, sir?
B: (1)_____
A: How old is he?
B: (2)_____
A: Do you want cars?
B: (3)_____
A: How about the toy plane?
B: (4)_____
A: What does your son like?
B: (5)_____
A: Then, I think he wants a robot. Boys like robots very much.
B: (6)_____
A: The one  near the window?
B: (7)_____
A: Here you are. This is a new model. It can walk and talk.
B: (8)_____
A: Yes. If you touch the nose, it sings.
B: (9)_____
A: Yes. This way, please. There are many over there.
B: (10)_____
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