皮皮学，免费搜题
登录
搜题
【单选题】
9在直流电机中,换向极的作用是()。A.
产生电机的主电动势
B.
改善电机的换向效果
C.
用于加强电枢反应的作用
D.
促进“环火”的生成。
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
反馈参考答案：
举一反三
【简答题】Children are used to the parties that consist of junk food, loud music and the like．However, today's environmental condition is serious, so to save our environment, we need to do our bit by sma...
【单选题】Their loud parties have recently caused a number of ________ from the other people in their building.
A.
determinations
B.
complaints
C.
congratulations
D.
attitudes
【单选题】Their loud parties have recently caused a number of _____ from the other people in the building.
A.
compositions
B.
communications
C.
competitions
D.
complaints
相关题目：
参考解析：
知识点：
题目纠错 0
发布
