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问题 填空题

焦距是镜头的（）至（）的距离。通常在照相机的镜头上标示出（）。如镜头焦距为55mm，有效口径为2.0，标示F=55mm或2.0/55。

答案

参考答案：焦点；光心；焦距数值

选择题

Alice， _______ university teacher from Australia, teaches me ______ English in her spare time.

A．an; /

B．a; the

C．an; the

D．a; /
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补全对话，情景问答
从A-G选项中选出五个句子补全对话，有两个为多余选项。

A: Hello, Jim. May I come in?
B: Oh, hello, John. Yes, come in, please.
A:    1    What's the matter?
B: My head hurts and I feel really hot.
A: Oh dear! Why don't you go to bed for a rest?
B: I can't.    2   
A: Shall I call tum and tell him you're ill?
B: Oh, yes, please.    3   
A: OK. I'll do that. Im going to the shops now. Can I get you some medicine?
B: Yes.    4   
A: Yes, of coruse. Is there anything else I can do?
B:    5    Thanks for your help.
A: See you later then. Take care !

A. His number is in the phone book.
B. No, I'll be all right.
C. Could you buy me a bottle of aspirin (阿司匹林), please?
D. It doesn't hurt very much.
E. You don't look very well.
F. I will play ping - pong with our teacher this afternoon.
G. You can keep in touch with him by e-mail.
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