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【单选题】
滑块1置于水平面2 上,当滑块1上作用一个与竖直方向成a角的驱动力F时,如下哪种情况下将发生自锁? (摩擦角记为ψ)( )。A.
a
B.
a>ψ
C.
a< 90 ° +ψ
D.
a> 90 ° +ψ
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【单选题】Wang Hua is said ____a new computer program recently, but I don’t know when she will finish it.
A.
to design
B.
to be designing
C.
to have been designing
D.
to have designed
【单选题】— Have you _____ Wang Hua to give up playing the computer games? — No. I have talked to him many times, but it didn't work. [ ]
A.
advised
B.
suggested
C.
allowed
D.
persuaded
【简答题】亚洲和欧洲合起来称________大陆。亚洲是世界第_____大洲。欧洲流经国家最多的河流是________河，亚洲流经国家最多的河流是_________河，在我国境内称___________ 。
【单选题】Wang Hua is an________from a vocational school.
A.
Chinese teacher
B.
English teacher
C.
math teacher
【单选题】Wang Hua has applied ______ the Communist Party of China.
A.
to join
B.
in joining
C.
for joining
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