Where is your mother? She's ____ home. [ ]
A. in
B. at
C. to
答案：B
________ Anirban Maitra, a professor at Oxford University, Jack’s success would not have been possible.
A．If it weren’t for
B．Were it not for
C．Had it not been for
D．If it hasn’t been for
当信号压力增加时，推杆向（）动作的叫正作用式执行机构。
A.上
B.左
C.下
D.右
