请问什么时候用 see sb doing sth 什么时候用 look at sb doing sth什么时候用 watch sb doing sth

请问什么时候用 see sb doing sth 什么时候用 look at sb doing sth什么时候用 watch sb doing sth 什么时候用see sb doing sth,什么时候用see sb to do sth要有例句,简要说明下, 英语概念题,求详解如何区分什么时候用see sb doing 什么时候用 see sb do 什么时候用see sb done sth? see,hear,notice之类的单词的用法什么时候加sb.do sth.什么时候加sb.doing sth. 用I see sb do sth 和I see sb doing sth造句.各两个 用3.see sb.doing4.there be doing造句中文 初中英语see sb doing sth 在被动可以用吗 用feel frustrate和see sb doing Sth造句 see look at 造句用see look athear listen tofind look forsee sb doing sthhear sb doing sth 造句 看见某事正在被做see怎么用?就是有see sb doing see sb dosee sth +什么？正在被做呢 see sb doing 和see sb do区别用法 see sb to do和see sb doing的区别? see sb do与see sb doing区别 see sb.do和see sb.doing 怎样区分? 关于see sb do和see sb doing的例句 see sb doing和see sb do有什么区别 see sb do see接从句?什么时候用see sb doing/do?什么时候see接从句?请参照：The students saw it____（happen/happened）when they were walking near the river.I could see the boys of Class Two____（play/played basketball）on the playg