在Windows操作系统中,()在窗口上工具栏内。
A.按钮
B.菜单
C.光标
D.图像
参考答案:A
The work of professional sectaries is so ______ that few people like to apply for it; it demands of not only high working efficiency bust also ______ available all the time. As a result, they are ______ great demand. [ ]
A. demanding; being; in
B. demanded; being; in
C. demanding; be; in
D. tiring; being; of
双集气管内的煤气压力应保持相等,防止煤气倒流。