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问题 选择题
若
a
=（x，2），
b
=（
1
2
，1），
c
=
a
+2
b
，
d
=2
a
-
b
，且
c
∥
d
，则
c
-2
d
等于（　　）
A．（-
5
2
，-5）		B．（
5
2
，5）		C．（1，2）D．（-1，-2）
答案

∵

c
=
a
+2
b
=（x+1，4），
d
=2
a
-
b
=（2x-
1
2
，3），
c
∥
d
．

∴3（x+1）=4（2-

1
2
），

解得x=1，

∴

c
c=（2，4），
d
=（
3
2
，3），

∴

c
-2
d
=（-1，-2），

故选D．

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翻译题

完成句子。

    阅读下列各小题,根据括号内的汉语提示，用句末括号内的英语单词完成句子。

1.It's universally acknowledged that never __________ (我们能期待) a bluer sky unless we create

   a less polluted world.(expect )

2.We breathed a sigh of relief at last.Had she known about the risks, she _____(也许没完成)with

   the operation.(go)

3.________ (急需钱), he tried to persuade her to marry him, but she changed her mind and

   declined.(desperate)

4.With ________(所有人抛弃)him, he went abroad and asked for shelter.(desert)

5.My dog is too fat.It's evident that I ________(不该喂)him with so much food.(feed)

6.______ (给我印象最深的) is the beauty of the white clouds floating in the blue sky.(strike)

7.I was very nervous because it was the first time that I ________ (受邀请) an opening banquet.(invite)

8.We wonder ________(是什么)caused so many strange things to happen.(it)

9._______ (毫无疑问)that honeybees communicate information of the feeding place to each other

   by dancing.(doubt)

10.It's likely that such a question, if it can be called a question, ________ (你提的), can't be

     answered by any human beings.(raise)
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