【单选题】 矩形花键按装配型式分为固定联接、紧滑动联接和滑动联接三种 ,如果 内、外花键之间要求有相对移动,而且移动距离长、移动频率高的情况,应选用配合间隙较大的( )联接 。
【单选题】Scientists are interested in the eyes of frogs because______.
A.
frogs' eyes are large and threatening
B.
frogs' eyes are extremely sharp
C.
frogs have compound eyes
D.
frogs can only see moving objects
【判断题】矩形花键按装配形式分为固定联接、紧滑动联接和滑动联接三种。
【判断题】矩形花键按装配型式分为固定联接、紧滑动联接和滑动联接三种,如果内、外花键之间要求有相对移动,而且移动距离长、移动频率高的情况,应选用配合间隙较大的滑动联接。
【单选题】承包人在索赔事项发生后的( )天以内应向工程师正式提出索赔意向通知书。
【单选题】He has small _____ and short _____. [ ]
【简答题】It is bad for your eyes to read in the sun. ______ the sun is bad for your eyes.
【单选题】Will was lying on the grass, _______the sky thick with stars.
C.
his eyes were fixed on