Japanese - Verbs

Japanese verbs (動詞 - dōshi) are a highly critical and, initially, complex part of the language due to their extensive system of conjugation. Unlike English, Japanese verbs change their form to express tense, negation, politeness, voice (passive, causative), command, desire, and potential ability.

Here is a breakdown of the key characteristics, groups, and forms of Japanese verbs.

1. Key Characteristics

• Always at the End: The main verb of a clause or sentence almost always comes at the very end (Subject-Object-Verb).
• No Subject-Verb Agreement: The verb form does not change based on who is performing the action (I, you, he, they, etc.).
• Two Politeness Levels: All verbs have both a Plain/Casual form (used with friends, family, or in writing) and a Polite form (used with strangers, superiors, or in formal settings).

2. Verb Groups (The Foundation of Conjugation)

Japanese verbs are categorized into three groups, and you must know a verb's group to correctly conjugate it.

Group	Japanese Name	Structure	How to Conjugate
Group 1	五段活用 (Godan Katsuyō) / U-Verbs	End in a u-vowel sound, except ru (e.g., のむ nomu, きく kiku).	The most complex; the last consonant/vowel changes.
Group 2	一段活用 (Ichidan Katsuyō) / Ru-Verbs	Always end in る (ru), preceded by an e or i sound (e.g., たべる taberu, みる miru).	The simplest; the る is simply replaced by the new ending.
Group 3	変格活用 (Henkaku Katsuyō) / Irregular Verbs	Only two main verbs are truly irregular.	Must be memorized.

Group 3 Irregular Verbs	Meaning
する (suru)	to do
くる (kuru)	to come

3. Core Conjugation Forms (The Verb Stem System)

Most conjugations branch off from a few fundamental forms.

A. Dictionary/Plain Form (Original Form)

• Use: Casual speech (friends, family), dictionaries, relative clauses (e.g., "the person who ate the apple").
• Example (Group 2): 食べる (taberu - to eat)
• Example (Group 1): 飲む (nomu - to drink)

A. Dictionary/Plain Form (Original Form)

• Use: Casual speech (friends, family), dictionaries, relative clauses (e.g., "the person who ate the apple").
• Example (Group 2): 食べる (taberu - to eat)
• Example (Group 1): 飲む (nomu - to drink)

B. Polite Form (ます-Form)

• Formation: Used to show politeness/formality.
  • Group 2 (Ru-Verbs): Drop the final る and add ます. (たべ + ます = たべます)
  • Group 1 (U-Verbs): Change the final u-vowel sound to the i-vowel sound and add ます. (のむ → のみ + ます = のみます)
• Use: Polite Present/Future Tense (Affirmative/Negative/Past)
  • たべます (eats/will eat)
  • たべません (doesn't eat/won't eat)
  • たべました (ate)
  • たべませんでした (didn't eat)

C. て-Form (Connecting Form)

• Use: The most versatile form, used to:
  • List actions (朝ごはんを食べて、学校に行きます - I eat breakfast, and go to school.)
  • Request (食べてください - Please eat.)
  • Express ongoing action (食べている - I am eating.)
  • Express permission (食べてもいい - May I eat.)
• Formation:
  • Group 2 (Ru-Verbs): Drop the final る and add て. (たべ + て = たべて)
  • Group 1 (U-Verbs): The form is highly irregular and involves complex sound changes (e.g., のむ → のんで, いく → いって). These must be memorized.

D. た-Form (Plain Past Tense)

• Use: The casual/plain past tense.
• Formation: Identical to the て-Form, but replacing て with た, and で with だ.
  • Group 2: たべ + た = たべた (ate)
  • Group 1: のむ → のんだ (drank)
  • Irregular: する → した, くる → きた

4. Advanced Conjugations (Potential and Passive)

Once the core forms are mastered, these are built upon them:

Form	Meaning	How it is Used
Potential	Ability ("can do")	Group 2: Drop る, add られる (たべられる - can eat). Group 1: Change u-vowel to e-vowel, add る (のむ → のめる - can drink).
Passive	The subject is acted upon ("is done")	Group 2: Drop る, add られる (たべられる - is eaten). Group 1: Change u-vowel to a-vowel, add れる (のむ → のまれる - is drunk).
Causative	Making or letting someone do something ("make/let do")	Group 2: Drop る, add させる (たべさせる - make someone eat). Group 1: Change u-vowel to a-vowel, add せる (のむ → のませる - make someone drink).
Volitional	Intention or Suggestion ("Let's do")	Plain: Change u-vowel to o-vowel, add う (いこう - Let's go). Polite: add ましょう (いきましょう - Let's go).

The key to mastering Japanese verbs is to first correctly identify the verb group and then drill the conjugation rules for the ます-form, て-form, and た-form, as almost every other structure is built upon these foundations.