单项选择题
A.steel guides B.steel shells C.steel bearing caps D.pig iron
The main bearing shells often have a thin （） of lead or...
单项选择题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
The main bearing shells are made of steel with a lining...
单项选择题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
The main bearing metal is a lining （）.A.inside the bear...
单项选择题The main bearing metal is a lining （）.
A.inside the bearing B.outside the bearing C.covering the crankshaft D.none of the above
