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單項選擇題

In each cylinder cover there are two or three holes for （）

A.the exhaust valves
B.the fuel valves
C.indicator cocks
D.the fuel pumps

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單項選擇題

In each cylinder cover is a large central opening for mounting （）

A.the indicating cock
B.the starting valve
C.air inlet valve
D.the exhaust valve

單項選擇題

In an ordinary four-stroke engine the exhaust valves open （）

A.after TDC
B.before TDC
C.after BDC
D.before BDC