堆取料机液压系统的中的流量控制阀,只有油量充足时阀体才起作用。
参考答案:对
妊娠时尿糖阳性不一定是糖尿病。
“Have you seen the film?” he asked me. →He asked me _______.
A.had I seen the film
B.have I seen the film
C.if I have seen the film
D.whether I had seen the film