单项选择题
A.value B.valuation C.valuable D.All above
（）on cargo lights.A.CloseB.SwitchC.OpenD.All above.
单项选择题（）on cargo lights.
A.Close B.Switch C.Open D.All above.
These goods shall be handled with （）.A.cautionB.poisono...
单项选择题These goods shall be handled with （）.
A.caution B.poisonous C.flammable D.dangerous
Before （）the harbour, all derricks must be secured prop...
单项选择题Before （）the harbour, all derricks must be secured properly.
A.leave B.leaved C.to leave D.leaving
