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單項(xiàng)選擇題

The main bearings are provided with thin-walled （）, lined with a copper-lead alloy.

A.steel guides
B.steel shells
C.steel bearing caps
D.pig iron

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單項(xiàng)選擇題

The main bearing shells often have a thin （） of lead or indium to provide a layer giving protection against corrosion.

A.flange
B.flash
C.plate
D.sheet

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

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