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單項(xiàng)選擇題

The main bearing shells are made of steel with a lining of bearing metal which may be white metal, copper-lead or aluminum-tin alloy What is the meaning of “which” in the sentence above?（）

A.main bearing shells
B.main bearing
C.steel
D.bearing metal

你可能感興趣的試題

單項(xiàng)選擇題

The main bearing metal is a lining （）.

A.inside the bearing
B.outside the bearing
C.covering the crankshaft
D.none of the above

單項(xiàng)選擇題

The machine has stopped rotating because the bearing （） the shaft.

A.seized
B.clogged
C.melted
D.inserted