be to do 和be doing的区别例如：My job is teaching.和My job is to teach.有什么区别啊?

be easy to do和 be easy doing 的区别 be to do和be doing的区别 be gonging to do和be doing的区别 be careful doing和be careful to do的区别? 用 be doing 和be doing to do 造句 三个 used to do,be used to doing和 be used to do的区别,并举例说明 be made to be doing 和be made to do的区别 be going to do和be doing和want to do 三者之间的区别 英语 have trouble+?be use to do 和 be use to doing区英语have trouble+?be use to do 和 be use to doing区别 to be doing 和 doing的区别 be devoted to do 和be devoted to doing的区别?呃 有be devoted to do be sure to do和be sure of doing 的区别be sure to do和be sure of doing的意义有什么不同 be doing和be going to do的区别be doing和be going to do都表示将来但是二者的区别是什么?那一个更表示肯定? be used to do和be used to doing的用法和区别 be afraid of doing 和 be afraid to do 区别 be about to do和be about doing 区别 be allowed to do和be allowed doing 什么区别 be left doing和be left to do怎么区别