keep后面是加doing还是todo

keep后面是加doing。keep doing sth（一直做某事）。例句：Keep doing the same thing over and over again（总是重复的做同一件事）。

keep doing例句：If marriage fails as often as it does，why do so many of us keep doing it（如果婚姻如它通常会发生的那样举步维艰的话，我们为什么还要这样继续下去）；Keep doing the same thing over and over again（总是重复的做同一件事）。