is about to do was about to do分别属于什么时态啊

is about to do was about to do分别属于什么时态啊 be about to do is about to do和will be有什么区别? He is not about to do that be to do be about to do 有什么区别 have to ,时态,Must,it is/was neccesary to do set about; set to do 将来时态的区别be going to;will do;be doing;be to do;be about to do be going to do、be about to do、be to do,这三者有什么区别? be about to do和mean to do和intend to do有什么区别 what about do还是what about to do? QUESTION about: all it has to do is stop raining.