操作技能的分类：1、连续的和不连续的动作技能2、封闭的与开放性的动作技能3、细微型与粗放型动作技能4、徒手型与器械性动作技能
参考答案：对
Tom doesn't like the film ________, but his parents like ________. [ ]
A. himself; it
B. itself; themselves
C. itself; it
D. himself; themselves
离心泵按泵轴布置方式主要分为（）。
A.单级泵和多级泵
B.单吸泵和双吸泵
C.卧式泵和立式泵
D.蜗壳泵和透平泵
