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【单选题】
所谓的扭曲环是指有倒角或角槽的活塞环，目的是使其在某些行程时与缸壁保持线性接触而具有刮油作用，这种刮油作用应发生在哪个行程？（）A.
进气行程
B.
作功行程
C.
压缩行程
D.
排气行程
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皮皮学刷刷变学霸
举一反三
【单选题】— Our class won the English speaking contest. — Congratulations! You _____ be very proud of it. [ ]
A.
can
B.
need
C.
would
D.
must
【单选题】— I came out first in the English Speaking Contest. — ________________________
A.
Congratulations!
B.
You can say it again!
C.
It’s very nice of you .
【单选题】There ______ an English speaking contest (演讲比赛) for middle school students in our city in early July. [ ]
A.
is going to
B.
will be
C.
will have
D.
is
【单选题】The shy girl has won the gold medal in the speaking contest, ______ I find hard to believe.
A.
that
B.
which
C.
who
D.
whom
【单选题】---Are you going to take part in the English speaking contest? ---_______. It’s too good an opportunity to miss.
A.
That’s for sure
B.
No problem!
C.
Why me?
D.
Why bother?
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