怎么区别to doing 和to do 一个是to+介词,一个是不定式,

to do和to doing的区别 be left doing和be left to do怎么区别 start to do 和 start doing 区别 to do和doing的区别 to do 和 DOING 有什么区别 doing和to do的区别 to do和doing做开头区别 doing和to do的区别 like to do 和like doing区别? to do 和doing放句首的区别 hope to do和doing区别 allow to do和 allow doing区别 like to do 和 like doing区别 require to do和require doing区别, want to do 和 want doing区别 practice doing sth.和 learn to do sth.它们有什么区别doing 和 to do?我该怎么去使用doing和to do?我不是很清楚. 怎么区别to doing 和to do 一个是to+介词,一个是不定式, sorry to do和sorry for doing区别sorry to do和sorry for doing 区别?