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问题 解答题
先化简，再求值：（x+2）（x-2）+（x+2）2，其中x=
1
2
．
答案

原式=x2-4+x2+4x+4=2x2+4x，

把x=

1
2
代入上式的：

原式=2×

1
2
2+4×
1
2
=
5
2
．

选择题

第一次鸦片战争结束时，清朝对外开放通商口岸最多的省份是

A．福建

B．广东

C．江苏

D．浙江
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补全对话，情景问答
选择正确的句子完成对话。
A. you will narrow your mind if you always live in the country for a long time.
B. But I feel that living in the city is more convenient
C. How do you think the life in the country?
D. How is it going these days?
Rose: Hi! Jim.          1         
Jim: It's great! I have been to the countryside for a vacation.
Rose: Really?        2          
Jim: I think it is so wonderful. The air is fresh and it is so quiet. What a good place to live in
Rose:         3         
Jim: I don't agree with you.  In the city, the air pollution and traffic problem make you sick.
Rose: I disagree with you. You will be open minded if you live in the city because the information  
        comes quickly, while         4          
Jim: I don't think so.
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