画剖视图,可以省略的情况有( )。
A. 单一剖切面通过对称面,且按投影关系配置,可以省略标注
B. 机件不对称,但按投影关系配置,可以省略箭头
C. 单一剖切面通过对称面,不按投影关系配置,可以省略标注
D. 机件不对称,且不按投影关系配置,不可以省略标注
Adventurous and hardworking, he was among the first to settle ___ is now St. Louis, Missouri.
A. at that
B. for where
C. by which
D. in what
He is very tired. He needs ___.
A.a day and a night rest
B.a day's and night's rest
C.a day and night's rest
D.rest of a day and a night
This broadcast comes to you ___ from the stadium.
A.live
B.lively
C.alive
D.living
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