【单选题】【消耗次数：1】
官能团羰基是（ ）。
①
碳碳双键
②
碳碳单键
③
碳氧双键
④
碳氧单键
参考答案：
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相关题目
【多选题】
实现碳达峰、碳中和的碳汇系统建设包括（）。
①
A.森林碳汇、海洋碳汇
②
B.湿地碳汇<br/>、冻土碳汇
③
C.水域碳汇、草地碳汇<br/>
④
D.耕地（农田）碳汇
随机题目
【单选题】
Most importantly, such an experience helps ____ a heightened sensitivity to other cultures and will bring about a greater appreciation of one’s own culture as well.
①
coach
②
forsake
③
foster
④
censor
【单选题】
She didn’ t come to the party last Sunday._____, she must
have made the party more exciting.
①
If she came
②
Would she come
③
Had she come
Did she come
【单选题】
Some companies have introduced flexible working time with less emphasis on pressure ____.
①
than more on efficiency
②
and more on efficiency
③
and more efficiency
④
than efficiency
【单选题】
In some cases, your instructor may tell you the topics ____ or may give you a choice of topics to write about.
①
in advance
②
ahead of
③
above al
④
right away
【单选题】
Nancy was surprised that they have ____. They
seemed to be a happy couple.
①
split up
②
broken down
③
fallen through
④
knocked out
【单选题】
— Whichsongdoyoulikebetter，Lucy?— IpreferthesongLittleApple ______ canattractmanypeople．
①
which
②
who
③
whom
④
where
【单选题】
Once ____, this power station will supply all the
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①
it being completed
②
it completed
③
completed
④
it completes
【单选题】
The Brownings have not ____ yet and I doubt whether they will come.
①
turned in
②
turned out
③
turned up
④
turned to
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The ____ in Janet’s character has hindered her
from advancement in her career.
①
weakness
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merit
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defect
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shortcoming