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【多选题】
发动机气门弹簧的作用有哪些?A.
保证气门弹簧可靠地工作。
B.
保证气门自动回位关闭而密封。
C.
保证气门与气门座的座合压力。
D.
吸收气门在开启和关闭过程中传动零件所产生的惯性力，以防止各种传动件彼此分离而破坏配气机构正常工作
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皮皮学刷刷变学霸
举一反三
【单选题】What will the man do this afternoon?
A.
He has an important meeting.
B.
He has a lunch appointment.
C.
He will check his schedule for openings.
D.
He will write a report.
【单选题】What do we know about the man from the conversation?
A.
He has never been to the beach.
B.
He is hard-working.
C.
He has never spent his weekend in the library.
D.
He wishes he had gone to the beach with the woman.
【简答题】A．No, he is not allowed to change his mind. B．Yes, he has the legal right to do so. C．No, because he has already displayed the goods. D．Yes, if the customer allows him to do so.
【单选题】— Do you think he can get the first prize for jumping? —Impossible now. He to do so, but he has just hurt his leg. [ ]
A.
would expect
B.
was expected
C.
has expected
D.
is expected
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