一个英语问题 keep up 和 keep on当“继续”讲有什么区别?

一个英语问题 keep up 和 keep on当“继续”讲有什么区别? 英语时态问题 have been doing 能等于 keep doing 么看到一个资料上说 在某人一直做某事时可以用 have been doing 也可用keep doing 这样对么 从时间概念上讲 ,have been doing 表示是过去到现在的时间 而 kee 英语,keep doing sth ,还是keep to do sth ,或者kee英语,keep doing sth ,还是keep to do sth ,或者keep do sth （英语）关于keep的几个词汇问题Failure is the mother of success.______ your courage.A.Keep onB.Keep upC.Keep back D.Keep up with 英语keep短语问题keep sb doing sth 和 keep sb from doing sth 的区别! stay up 和keep up的区别 keep off 和keep out 和keep up 和keep from的区别 keep up 、keep on 、keep out 、keep from的区别、和例句 说出keep up和keep on的不同用法 keep on和keep up有什么区别? keep up keep up keep up 有关keep和up 的短语 Keep up with 和 Catch up with 有什么不同?记得其中有一个是“想到”的意思 keep up with和 catch up with怎么区别? keep up with 和catch up with 有区别吗 keep up with和catch up的区别