柴油机运转初期产生的磨合拉缸,其损伤部位一般在气缸套与()工作表面。
A.活塞
B.活塞裙
C.活塞环
D.活塞环及活塞裙
参考答案:C
Kathy __________a lot of English idioms by watching documentaries made by BBC.
A. picked up B. took up C. made up D. turned up
货车车钩各部运用限度是如何规定的?