The cylinder liners are made of （） and the cylinder surfaces are sometimes chromium-plated.

[单选题]The cylinder liners are made of _____ and the cylinder surfaces are sometimes chromium-plated.A．steelB．copperC．cast ironD．stainless steel

[单选题]The withdrawing of the cylinder liners, in general, depends on their （）.This may amount to approximately 1/120 of the diameter in some engines.A . correct maneuveringB . wearC . working efficiencyD . maintenance

[单选题]A number of cylinder liners are enclosed in one cast iron casing to form a （）.A . cylinder coverB . cylinder blockC . cylinder frameD . bed-plate

[单选题]The cylinder covers and the liners are bolted together by means of （）.A . bolts welded into the cylinder headB . bolts welded into the cylinder framesC . studs screwed into the cylinder headD . studs screwed into the cylinder frame

[单选题]（） the cylinder walls, the heat passes through them by conduction.A . When receiving byB . When received byC . In order to receivingD . In order to receive

[主观题]Thepresidentmadea_______speechattheopeningceremonyofthesportsmeeting,whichencouragedthesportsmengreatly.A．)vigorousB)tediousC．)flatD)harsh

[单选题]The author has made a significant ____ to explain various issues regarding the web and its contents.A．reviewB．contactC．attemptD．comment

[单选题]Melissa and LoveLetter made use of the trust that exists between friends or colleagues. Imagine receiving an(71)from a friend who asks you to open it. This is what happens with Melissa and several other similar email(72). Upon running, such worms usu

[单选题]Our president made a(n) ____ speech at the opening ceremony of the sports meeting which encouraged the sportsmen greatly.A． indifferent B inspiring C flat D dry

[单选题]The ports are drilled in the liners at an angle of approx 20℃ the result being that （） is given a rotary movement.A . the scavenging airB . the exhaust gasesC . the mixed airD . the spray oil