The cylinder liners are made of （） and the cylinder surfaces are sometimes chromium-plated.
举一反三
- In order to increase the wearing resistance， the cylinder liner surfaces are sometimes （）.
- The cylinder covers and the liners are bolted together by means of （）.
- The withdrawing of the cylinder liners， in general， depends on their （）.This may amount to approximately 1/120 of the diameter in some engines.
- Each cylinder is closed at the top by a （）， made of a special heat-resistant steel.
- The top of the cylinder block is covered with the cylinder head. ( )