要求机床工作台往复运动速度相同时,应采用()液压缸
A.双出杆
B.差动
C.柱塞
D.单叶片摆动
参考答案:A
—How much ________ the sweater?
—________ fifty yuan. [ ]
A. is, It's
B. are, They're
C. is, They're
D. are, It's
水蛭、虻虫的共同功效是()
A.利尿通淋
B.活血调经
C.破血逐瘀
D.散结消癥
E.通经下乳