In English, we say "start eating," "keep writing," "finish reading." In Japanese, you literally fuse two verbs into one word. This is called a compound verb (複合動詞).
The Core Idea: Conjunctive Form + Suffix Verb
The recipe is simple:
Front verb's conjunctive form (ます-stem) + Suffix verb
For example:
- 書く conjunctive form = 書き (書きます → drop ます → 書き)
- 書き + 始める = 書き始める (start writing)
Just one step: turn the front verb into its conjunctive form (ます-stem), then attach the suffix verb directly.
The Big Four Suffix Verbs
| Suffix Verb | Reading | Meaning | Compound Meaning |
|---|---|---|---|
| 始める | はじめる | to begin | start doing something |
| 続ける | つづける | to continue | keep doing something |
| 終わる | おわる | to end | finish doing something |
| 過ぎる | すぎる | to exceed | overdo something |
Examples for Each
〜始める: Start Doing
| Front Verb | ます-Stem | Compound | English |
|---|---|---|---|
| 書く | 書き | 書き始める | start writing |
| 食べる | 食べ | 食べ始める | start eating |
| 飲む | 飲み | 飲み始める | start drinking |
| 読む | 読み | 読み始める | start reading |
雨が降り始めました。 → It started raining.
〜続ける: Keep Doing
| Front Verb | ます-Stem | Compound | English |
|---|---|---|---|
| 書く | 書き | 書き続ける | keep writing |
| 食べる | 食べ | 食べ続ける | keep eating |
| 走る | 走り | 走り続ける | keep running |
| 勉強する | 勉強し | 勉強し続ける | keep studying |
３時間走り続けました。 → I kept running for three hours.
〜終わる: Finish Doing
| Front Verb | ます-Stem | Compound | English |
|---|---|---|---|
| 書く | 書き | 書き終わる | finish writing |
| 食べる | 食べ | 食べ終わる | finish eating |
| 読む | 読み | 読み終わる | finish reading |
宿題を書き終わりました。 → I finished writing my homework.
〜過ぎる: Overdo It
| Front Verb | ます-Stem | Compound | English |
|---|---|---|---|
| 飲む | 飲み | 飲み過ぎる | drink too much |
| 食べる | 食べ | 食べ過ぎる | eat too much |
| 寝る | 寝 | 寝過ぎる | oversleep |
昨日飲み過ぎました。 → I drank too much yesterday.
過ぎる can also attach to adjectives:
| Adjective | Compound | Meaning |
|---|---|---|
| 高い | 高すぎる | too expensive |
| 甘い | 甘すぎる | too sweet |
| 静か | 静かすぎる | too quiet |
For い-adjectives, drop the い then add すぎる. For な-adjectives, attach すぎる directly.
How to Form the ます-Stem: Quick Reference
| Verb Type | Dictionary Form | ます-Stem | Rule |
|---|---|---|---|
| Godan (く) | 書く | 書き | う-row → い-row |
| Godan (む) | 飲む | 飲み | う-row → い-row |
| Godan (る) | 走る | 走り | う-row → い-row |
| Ichidan | 食べる | 食べ | drop る |
| する | する | し | irregular |
| 来る | 来る | 来(き) | irregular |
Godan verbs: shift the final kana from the う-row to the い-row (same as when attaching ます). Ichidan verbs: just drop る.
Compound Verbs Conjugate Like Regular Verbs
Once fused, a compound verb behaves like a normal verb. The suffix verb determines the conjugation type:
| Compound Verb | Type | ます-Form | ない-Form |
|---|---|---|---|
| 書き始める | Ichidan | 書き始めます | 書き始めない |
| 飲み過ぎる | Ichidan | 飲み過ぎます | 飲み過ぎない |
| 書き終わる | Godan | 書き終わります | 書き終わらない |
始める, 続ける, and 過ぎる are ichidan verbs; 終わる is a godan verb.
Wrap-Up
- Compound verb = front verb ます-stem + suffix verb
- The ます-stem is just the ます-form minus ます
- The Big Four: 始める (start), 続ける (continue), 終わる (finish), 過ぎる (overdo)
- 過ぎる also works with adjectives to mean "too..."
- Conjugate the compound verb based on the suffix verb's type
Practice
Q1. Combine 食べる and 始める into a compound verb.
Answer
食べ始める
食べる's ます-stem is 食べ (drop る), then attach 始める → 食べ始める (start eating).
Q2. What does 飲み過ぎました mean?
Answer
Drank too much.
飲み (ます-stem of 飲む) + 過ぎる (overdo) = 飲み過ぎる (drink too much). ました is the polite past tense.
Q3. Say "keep studying" in Japanese (勉強する + 続ける).
Answer
勉強し続ける
する's ます-stem is し, then attach 続ける → 勉強し続ける.