clean的过去式和过去分词是什么
clean的过去式是cleaned,过去分词也是cleaned。
过去式用法
作为规则动词,clean的过去式在词尾加-ed构成。例如:
She cleaned the room yesterday.她昨天打扫了房间
They cleaned the windows before the storm.暴风雨前他们擦了窗户
过去分词用法
过去分词cleaned可用于成时和被动语态:
现在成时
I have cleaned the kitchen twice this week.这周我已经打扫厨房两次了
被动语态
The floor was cleaned by the cleaning staff.地板由保洁人员打扫过了