The standard size of the containers is （）high.……

单项选择题This is deck cargo. （）stow it in the holds.

A.Not
B.Notto
C.Don’t
D.Can

单项选择题Before leaving the harbour, all derricks must be （）properly.

A.tightened
B.secured
C.unfastened
D.loaded

单项选择题（）operation, any obstacles in the way of hatches must be removed and cleaned.

A.Before
B.During
C.After
D.Within

单项选择题Each （）consists of two or more panels.

A.cover
B.hatch
C.derrick
D.winch

单项选择题Keep a close watch on（） cargo.

A.value
B.valuation
C.valuable
D.All above