One of the challenges when starting Japanese is learning verb conjugation. How do I make a verb negative or past tense? A quick search of wikipedia produces a page with over ten large tables which are intimidating and not well explained. When studying for the JLPT, you already need to memorize hundreds of words, kanji, and grammar patterns. So, large conjugation tables……no thank you.

Instead I summarize verb conjugation into a set of quick and easy rules plus one medium sized table. This requires significantly less memorization. As with all rules (as well as large conjugation tables) there are exceptions. I try to list the ones I can think of, but there are more, especially at the higher levels.

The following rules build on one another so I recommend you learn them in order.

A note for Japanese linguists: These rules are meant to help Japanese learners (especially at the N5 level). They are not linguistically correct.

Prerequisite: Japanese Alphabet Rows

The following table is one that Japanese learners probably already know: the Japanese alphabet in hiragana. (I wrote it in western style, from left to right rather than the traditional Japanese style that would go from right to left.) As you’ve probably already learned in Japanese class, each row consist of characters with the same vowel sound. For example in the first row, which I’ve colored red and labeled as the あ-Row, all characters contain the vowel sound あ. Ka, sa, na, ta, ra, wa, etc. all have the “a” sound. You probably already know this, but I’m pointing it out because we will use this table in formulating the verb conjugation rules.

0. V-る (Dictionary Form)

There is no conjugation to learn here, but it is important because dictionary form is the starting point from which our rules will derive. As the name suggests, this is the form you find in the dictionary. It always ends with an う-sound; the last character is from the う-Row.

1. V-て (Te-Form)

Here is the one table you must memorize. The last character of all verbs in dictionary form come from the う-Row. Simply replace the last character with what is listed in the following table and you get te-form.

Iru/Eru Verbs

One thing that I must explain. The first row denotes iru/eru verbs. These all end with iru or eru. Examples include 食たべる and 借かりる. Note that some verbs such as 売うる end with る, but are not iru/eru verbs.

There are a few exceptions where verbs end with iru or eru, but are not iru/eru verbs. These verbs should be treated as if they end with る (i.e. they get conjugated to って). Exceptions include: 切きる、知しる

V-て Conjugation Table

Last Character Of Dictionary Form	Te-Form Replacement	Example
Iru/Eru Verbs: （い）る、（え）る	て	食たべる	食たべて
う、つ、る	って	買かう 売うる	買かって 売うって
ぶ、む、ぬ	んで	飲のむ	飲のんで
く	いて	書かく	書かいて
ぐ	いで	泳およぐ	泳およいで
す	して	貸かす	貸かして
Exception: 行いく	行いって
Exception: する	して

Now for the easy rules.

2. V-ない – Negative

• Iru/Eru Verbs: Drop る, add ない
  Ex. 食たべる ⇒ 食たべない
• All Others: Change last character from う-Row to あ-Row, add ない
  Note: う becomes わ
  Ex. 買かう ⇒ 買かわない
  Ex. 分わかる ⇒ 分わからない

In addition to being used as a verb, the negative form can also be used (and further conjugated) as an い-adjective.
Ex. 分わからない本ほんがあそこにあります。 The book I don’t understand is over there.

Note about ～ないでください

On the N5 you will encounter the grammar pattern ～ないでください (Please do not ～).

3. V-なかった – Past Negative

If you want the past negative form, no need to memorize more rules. Simply treat the negative form as an い-adjective and make it past-tense. (Coming soon: N5 – How to conjugate adjectives.)

Ex. 買かわない ⇒ 買かわなかった
Ex. 食たべない ⇒ 食たべなかった

4. V-た – Past

• Use the て-Form and replace て with た.
  Ex. 食たべて ⇒ 食たべた
  Ex. 買かって ⇒ 買かった
  Ex. 分わかって ⇒ 分わかった

5. V-Stem

This is an important form because it is the basis for some of the grammar patterns found on the N5. Additionally all polite forms can be derived from V-Stem.

• Iru/Eru Verbs: Drop る
  Ex. 食たべる ⇒ 食たべ
• All Others: Change last character from う-Row to い-Row
  Ex. 買かう ⇒ 買かい
  Ex. 分わかる ⇒ 分わかり

Example Usage: ～たいです。

One place where V-Stem gets used is in the grammar pattern ～たいです (Want to ~). You simply start with V-Stem and add たい to it.
Ex. この本が買いたいです。 (I want to buy with book.)

Example Usage: ～ながら

Another place V-Stem is used is ～ながら (While ~). Again, simply start with V-Stem and add ながら. Pretty easy once you know how to get V-Stem.
Ex. 音楽を聞きながら日本語を勉強します。 (I study Japanese while listening to music.)

6. V-ます – Polite Present

• Start with V-Stem, add ます
  Ex. 買かい ⇒ 買かいます
  Ex. 食たべ ⇒ 食たべます

7. V-ません – Polite Negative

• Start with V-Stem, add ません
  Ex. 買かい ⇒ 買かいません
  Ex. 食たべ ⇒ 食たべません

8. V-ました – Polite Past

• Start with V-Stem, add ました
  Ex. 買かい ⇒ 買かいました
  Ex. 食たべ ⇒ 食たべました

9. V-ませんでした – Polite Past Negative

• Start with V-Stem, add ませんでした
  Ex. 買かい ⇒ 買かいませんでした
  Ex. 食たべ ⇒ 食たべませんでした