Conjugating する (plain/dictionary form)
する/suru (“to do”) is one of two irregular Japanese verbs. You will have to use this verb almost every time you speak Japanese, so you should become familiar with. You are going to be spending a lot of time with する!
non-past (do; does)
する suru
non-past negative (does not; will not)
しない shinai
past (did)
した shita
past negative (didn’t; did not)
しなかったshinakatta
Conjugating 来る (plain/dictionary form)
来る/kuru (“to come”) along with する/suru , is another common irregular verb. It also has a peculiar conjugation:
non-past (come; comes)
来る kuru
non-past negative (does not come; will not come)
来ない konai
past (came)
来た kita
past negative (didn’t come)
来なかったkonakatta