Another video in the ‘permissions’ series. Here we’ll be looking at しないとならない, しなければならない, しなくてはならない which are all used to talk about things that must be done.
Update: I’ve done some reading that points out that using the と conditional with ならない is weird for this type of construction. I agree and was just going off Tae Kim’s grammar guide, but of course Tae Kim is not a native speaker so not everything in his guide is necessarily accurate. The other 2 constructions are valid.
