Basic Verb Conjugation
There are three categories of verbs in Japanese: ru-verbs, u-verbs, and irregular verbs. Ru and u verbs follow regular conjugation:
Ru-verbs u-verbs
verb bases tabe iku
dictionary forms たべる (to eat) いく(to go)
present, affirmative たべます いきます
present, negative たべません いきません
stems たべ いき
There are only two irregular verbs in Japanese: する and くる. They are cojugated as follows:
dictionary forms する くる
present, affirmative します きます
present, negative しません きません
stems し き
Ru-verbs are so called because you add the suffix ru to the verb base to form the dirctionary form.
U-verbs can be broken down into the base and the suffix. The long form are formed with the base plus suffixes imasu and imasen.