单项选择题
A.stopping B.being stopped C.to stop D.to be stopped
The two-stroke cycle begins with the piston coming up f...
单项选择题The two-stroke cycle begins with the piston coming up from the BDC, with the scavenging ports in the sides of the cylinders being （）.
A.open B.uncover C.covered D.closed
Hearing a strong noise, （） at once.A.the engine stopped...
单项选择题Hearing a strong noise, （） at once.
A.the engine stopped B.the engine was stopped C.he stopped the engine D.he had stopped the engine
（） that everything in the engine crankcase is correct, ...
单项选择题（） that everything in the engine crankcase is correct, start up the crankcase lubricating oil pump.
A.To satisfy B.To be satisfied C.After satisfying D.After being satisfied
