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【单选题】
According to paragraph 1, what was a common claim about ecological communities before the early twentieth century?A.
Every species in a community has a specific role in that community.
B.
It is important to protect communities by removing certain species.
C.
A precise balance is difficult to maintain in an ecological community.
D.
It is necessary for new species to be added quickly as ecological communities develop.
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举一反三
【单选题】According to a recent American study, people start losing their mental ability______.
A.
in their early teens
B.
in their mid-sixties
C.
in their mid-twenties
D.
in their early thirties
【单选题】It is not easy for a great star to _____ when losing his ability of taking care of himself. [ ]
A.
pull through
B.
let out
C.
wake up
D.
take up
【单选题】what is the problem with the young people in Britain?
A.
They are losing their ability to remain confident.
B.
They are losing their ability to express themselves clearly and accurately.
C.
They are unable to study a foreign language.
D.
They are unable to lose weight.
【简答题】他认为有必要制定一部“布伦特法”,以约束不人道的超时工作现象。
【单选题】Education is the ability to listen to almost anything without losing your (temper).
A.
交易
B.
跟踪
C.
坏脾气；使暖和
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