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问题 填空题

若|a+b|=|a-b|，则a与b的夹角为_______________.

答案

90°

解：因为|a+b|=|a-b|，利用向量的几何意义可知，a与b的夹角为90°

完形填空

Dear Tony,

Thank you very much _____ your letter. Shanghai ______ beautiful! I like Shanghai _______ I like China. Now I’m fine and I’m busy _____ my lessons. I have seven classes every day. There are ______ in the morning and three in the afternoon. I have nine subjects this term. I like math, biology and history. My _____ subject is science, because it’s very interesting. Yes, my English is very _____, and I like it, but I _____ like Chinese, because it is too difficult ______ me, and I can’t learn it well. Do you play soccer? Can you _____ Chinese? I hope you can come to China one day.

Bob

小题1:A.to     B.of      C. for

小题2:A.be     B.is      C.are

小题3:A.so     B.but     C.and

小题4:A.at     B.about   C.with

小题5:A.four   B.three    C.two

小题6:A.best   B.favorite   C.like

小题7:A.good   B.well     C.better

小题8:A.isn’t    B.doesn’t   C.don’t

小题9:A.for     B.to       C.about

小题10:A.tell    B.say      C.speak
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比较题

(1).黄芩（）
(2).葛根（）
(3).生姜（）
(4).白芷（）

A.解表药

B.解肌药

C.两者均是

D.两者均不是
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