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单选题
The bore of each cylinder is formed in a liner which can be （） when worn out.
A
welded
B
replaced
C
drilled again
D
bored
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quality of fuel injectedC
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单选题Which of the following statements concerning cylinder liner wear is true?（）A
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cooling waterB
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refrigerantD
lubricate oil
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单选题The cylinder is fitted with internal liner so that a water space is left （） the liner and the outer wall.A
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amongC
inD
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shorten the ring break-in periodC
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单选题The exhaust ports are located around the lower part of the cylinder liner, （）the products of combustion are driven by scavenging air.A
in whichB
by whichC
through whichD
from which
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