自動詞・他動詞 (intransitive verbs・ transitive verbs)

💡 The Big Picture: Intransitive vs. Transitive Verbs

In Japanese, many verbs come in pairs. The main difference comes down to who or what is doing the action, and whether an object is involved.

• 自動詞 (Jidooshi) — Intransitive Verbs: The action happens automatically or by itself. There is no direct object.

• 他動詞 (Tadooshi) — Transitive Verbs: Other people or forces do the action to something or someone else.

🔍 How to Tell Them Apart (The Easy Trick)

Think of the English words "Intransitive = Intrinsic/Independent" (happens on its own) and "Transitive = Transfer"(energy is transferred from an agent to an object).

1. Check the Sentence Structure

Type	Japanese Particle	English Equivalent	Example
自動詞 (Jidooshi)	が (ga) or は (wa)	Subject + Verb	ドアが開く (The door opens.)
他動詞 (Tadooshi)	を (o)	Subject + Object + Verb	ドアを開ける ([I] open the door.)

🔑 Key Takeaway: If you see を (o), it is almost always a Transitive Verb (他動詞) because something is acting upon an object!

⚡ Common Verb Pairs to Remember

Here are a few classic pairs to see how they work in real life:

Action	Intransitive (自動詞 - Happens by itself)	Transitive (他動詞 - Someone does it)
Open	開く (aku) — ドアが開く (The door opens)	開ける (akeru) — ドアを開ける (Open the door)
Close	閉まる (shimaru) — ドアが閉まる (The door closes)	閉める (shimeru) — ドアを閉める (Close the door)
Turn on	つく (tsuku) — 電気がつく (The light comes on)	つける (tsukeru) — 電気をつける (Turn on the light)
Enter / Put in	入る (hairu) — 部屋に入る (Enter the room)	入れる (ireru) — 物を入れる (Put things in)

🧠 Quick Summary Formula

• [ Thing ] + が + 自動詞: Something happens (Focus is on the state or result).

• [ Person ] + が/は + [ Thing ] + を + 他動詞: Someone does something to an object (Focus is on the action).