单项选择题
A.surface fatigue B.fretting corrosion C.heavy overloading D.gear misalignment
The following preparations are essential for any （） of ...
单项选择题The following preparations are essential for any （） of marine diesel engine before it may be started.
A.doing B.make C.turn D.operating
The diesel engine consumes considerably less fuel than ...
单项选择题The diesel engine consumes considerably less fuel than the steam engine for equal output, （） enables a motor-ship to load more cargo.
A.why B.which C.in which D.on which
It was （）midnight that we removed the trouble and went ...
单项选择题It was （）midnight that we removed the trouble and went back to our cabin.
A.until B.not until C.not before D.not after
