压缩机的容积效率是指( )。
A.实际输气量与理论输气量的比值B.理论输气量与实际输气量的比值C.实际输气量与理论排气量的比值D.理论输气量与实际排气量的比值
参考答案:A
The cousins are alike in age, but _____ they are as different as day and night. [ ]
A. anyhow
B. besides
C. otherwise
D. moreover
注射肉毒素时,应尽量避免累及的肌肉有()
A.额肌
B.颧大肌
C.提上唇鼻翼肌
D.降下唇肌
E.笑肌