Transitive vs Intransitive Verbs: The "Open" Dilemma

"Door Opens" vs "Open Door"

In English, the verb "open" is used for both "I open the door" and "The door opens". In Japanese, these are two completely different verbs! Using the wrong one changes the meaning entirely.

1. Transitive (Tadoushi - 他動詞) - ACTION

• Kanji: "Other" (Ta).
• Concept: Someone actively does something TO an object.
• Particle: Always WO (を). (Action acting ON something).
• Model: Subject -> Acts on -> Object.
• Examples:
  • I open the door: Door wo Akeru.
  • I break the cup: Cup wo Kowasu.
  • I turn off the light: Denki wo Kesu.

2. Intransitive (Jidoushi - 自動詞) - STATE/NATURE

• Kanji: "Self" (Ji).
• Concept: Describes the state or natural change of the subject. We don't care WHO did it, we just focus on WHAT happened to the object.
• Particle: Always GA (が).
• Model: Subject -> Changes naturally.
• Examples:
  • The door opens (Automatic door): Door ga Aku.
  • The cup breaks (It's broken): Cup ga Kowareru.
  • The light turns off: Denki ga Kieru.

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3. Quick Identification Tips (The 70% Rule)

How to guess which is which just by looking?

Intransitive Suffix	Transitive Suffix	Examples
-aru	-eru	Kakaru (Hang) - Kakeru (Hang sth) Tomaru (Stop) - Tomeru (Stop sth)
-reru	-su	Kowareru (Break) - Kowasu (Smash) Taoreru (Fall) - Taosu (Knock down)
(Irregular)	-su (Always Transitive)	Kesu (Erase), Dasu (Extract)

Magic Cheat:

• Ends in -SU? -> 100% Transitive (You do it).
• Ends in -ARU? -> Likely Intransitive (It happens).