锥形活套连头:watch sb do sth 和watch sb doing sth 的区别

watch sb do sth 和watch sb doing sth 的区别 watch sb. do sth. 与 watch sb. doing sth.的区别 watch sb. to do sth.的句型有什么? watch sb. to do sth.的句型有什么? aught sb do sth.. take sb do sth help sb to do sth和help sb do sth请问什么意思 hear sb do sth 和 hear sb do sth 有什么区别？ make sb do sth 和 let sb do sth的区别? help sb. to do sth这个to是可以省略,那么make/watch/let/please... sb. do sth这个to 是不是必须省略?