机械密封中,动环是与轴一起旋转的环形零件,()是固定在端盖或密封腔上的环形零件。
参考答案:静环
(2013·太原一模)—Who is standing over there?
—It must be ________ from an express company.
A.everybody
B.somebody
C.nobody
D.anybody
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