单项选择题
A （）is at the end of the cargo runner for picking up the load.
A.sling B.hook C.block D.tackle
单项选择题 The （）is fixed at the bottom of the derrick.
单项选择题 The （）is pumped onto the ship at the loading port by shore pumps.
单项选择题 The standard size of the containers is （）high.
