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问题 解答题
化简求值：2（3a2-5b）-[-3（a2-3b）]，其中a=
1
3
，b=-2．
答案

2（3a2-5b）-[-3（a2-3b）]，

=6a2-10b+3（a2-3b），

=6a2-10b+3a2-9b，

=9a2-19b，

当a=

1
3
，b=-2时，原式=9×（
1
3
）2-19×（-2）=39．

选择题

— Will you stay for lunch? 

— Sorry, ______. My brother is coming to see me. [ ]

A. I mustn't

B. I can't

C. I needn't

D. I won't

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填空题

介词填空，用in, on, at, of, about填空。

1. Look ________ the color picture ________ page 1.

2. Are there any books ________ China?

3. ________ the morning ________ June 1st we had a party.

4. ________ Monday morning we have a geography class.

5. ________ the morning I often get up ________ six.

6. Jim was born ________ January 13, 1989.

7. Sally was born ________ April, 1995. 

8. He is watching a football game ________ TV.

9. What ________ visiting the museum?

10. John is busy. He's ________ work.

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