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單項選擇題

The sealing rings are in four parts and pressed together around the piston rods by means of （）.

A.nuts
B.bolts
C.coil springs
D.stuffing boxes

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單項選擇題

The scavenging box is built of a number of sections provided with vertical flanges enabling them （） together to form two blocks.

A.being bolted
B.bolted
C.bolting
D.to be bolted

單項選擇題

The scavenging air ports are located at （） that they are just exposed by the upper edge of the piston when the piston is in the bottom dead center position.

A.so a height
B.such a height
C.so high
D.such high

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