keep doing sth 和keep on doing sth 有什么区别

keep doing sth 和keep on doing sth 有什么区别

1、keep doing sth. 坚持做某事
强调状语的继续,常与表示延续动作的动词与静止状态的动词连用,如(hope,think,wonder,dream,sit,stand,lie,sleep等)
例句：
1.1、He kept eating/ smiling/ walking.他一直在吃/笑/走.
1.2、She keep running她一直在跑（没停过）

2、keep on doing sth. 坚持做某事
表示动作反复,强调动作与动作之间有间隔,常与表示短暂动作的动词连用.
例句：
2.1、The boy kept watching the passing traffic at the gate.
这个男孩在门口不停地看着过往的车辆.
2.2、He kept on ringing me up,but I don't want to keep in touch with him any more. 他不断地给我打电话,可我不想和他保持联系了.

3、keep doing / keep on doing 区别
3.1、均可表示“继续做某事,反复做某事”,可互换,只是 keep on 更加强调时间的间隔性和动作的反复性,及某人做某事的决心.
例句：He kept /kept on working until midnight though he was tired.
他一直工作到半夜，尽管他已经很累了。
The boy kept /kept on asking some silly questions in class.
这个男孩在课堂上一直问一些愚蠢的问题。
3.2、若表示一连续不段的动作,或某一动作的持续状态,只宜用keep doing .
例句：They kept standing outside the room during all the meeting.
在开会期间，他们一直站在房间外面。（某一动作的持续状态）
Keep lying here; I will be back soon.
一直躺在这里,我很快就会回来。（一连续不段的动作）
3.3、若表示今后或将来继续做某事,则只宜用keep on doing .
例句：We must keep on working hard in the coming new year.
在新的一年里，我们必须继续努力工作 。（将来继续做某事）
He kept on smoking though we advised him to stop to smoke.
尽管我们劝他戒烟，但他还是坚持抽烟。（今后或将来继续做的事情）

keep doing sth.坚持做某事 强调状语的继续，常与表示延续动作的动词与静止状态的动词连用。
keep on doing sth.表示动作反复，强调动作与动作之间有间隔，常与表示短暂动作的动词连用。 “坚持做某事”，克服困难继续坚持。 

keep doing / keep on doing
1) 均可表示“继续做某事,反复做某事”,可互换,只是 keep on 更加强调时间的间隔性和动作的反复性,及某人做某事的决心.
He kept on working until midnight though he was tied.
The boy kept /kept on asking some silly questions in class.
2) 若表示一连续不段的动作,或某一动作的持续状态,只宜用keep doing .
She kept waving to her husband until he was out of sight.
They kept standing outside the room during all the meeting.
Keep lying here; I will be back soon.
3) 若表示今后或将来继续做某事,则只宜用keep on doing .
We must keep on working hard in the coming new year.
He kept on smoking though we advised him to stop to smoke.