无码高清视频|成人自拍视频|欧美成人午夜无码A片秀色直播|草美女视频网站|美女被操网站在线观看

單項(xiàng)選擇題

Prior to running the hydraulic pump, examine the system carefully and ensure that the lever of control valves is in () position.

A.neutral
B.end
C.opening
D.closure

微信掃碼免費(fèi)搜題