A friendly introduction to the main verb groups, forms and terminology used throughout this site.
The main verb normally appears at or near the end of a Japanese sentence.
The verb form does not change according to whether the subject is I, you, he, she or they.
The non-past form can describe present actions, habits or future events, depending on context.
The dictionary form is the basic, informal form under which a verb is listed in a dictionary. In romaji it always ends in an u sound—for example, taberu (to eat), iku (to go) and arau (to wash).
Although all three examples end in an u sound, their final Japanese kana are different: る (ru), く (ku) and う (u).
Romaji is the system used to write Japanese sounds with the Latin alphabet; the word literally means “Roman letters”. This site includes romaji to make the conjugations accessible to learners who are still becoming familiar with hiragana, katakana and kanji.
Romaji is useful as a learning aid, but it is worth gradually moving towards Japanese script because kana show the structure and changing endings of verbs more clearly.
You can also read the original blog post Romaji is for wimps.
Japanese verbs are usually divided into two main regular groups, plus a small irregular group. Knowing the group tells you how the verb ending changes when it is conjugated.
Godan verbs are sometimes called consonant-stem or u-verbs. The final kana changes within its kana row when different forms are made, using all five vowel sounds—hence godan, meaning “five steps”.
Most verbs that do not end in -iru or -eru belong to this group, although there are important exceptions.
View Godan verbsIchidan verbs are sometimes called vowel-stem or ru-verbs. Their dictionary form generally ends in -iru or -eru, and most conjugations are formed by removing the final る.
Ichidan means “one step”, reflecting the simpler, more consistent change to the verb ending.
View Ichidan verbsする (suru, to do) and 来る (kuru, to come) are the two principal irregular verbs.
The existence verbs ある (aru) and いる (iru), and the copula です (desu), are often taught alongside one another because they express existence or states of being. See the guide to Japanese existence and being expressions.
The form you choose in Japanese depends on the situation and your relationship with the listener. This site concentrates on the two most commonly encountered levels: plain and polite.
The polite -masu form is a safe choice in many everyday situations, particularly with people you do not know well or where a degree of formality is appropriate.
The plain form is common between friends and close family, when speaking to children, and in many informal settings. It is also widely used inside longer grammatical constructions, so “plain” does not always mean casual or impolite.