Plain 〜たい is reserved for the speaker — I want to. So the moment you need to say what someone else wants to do, Japanese hands you a different tool: 〜たがる. 弟は帰りたがっている "my brother wants to go home"; 子供がお菓子を食べたがる "the kid wants to eat sweets." The extra syllables がる are not decoration. They mean "to show signs of," and they turn a private feeling you cannot see into an observable behavior you can — which is precisely the permission slip you need to talk about another person's wants at all.
Why たい alone won't do
Japanese treats inner states — cravings, aches, wishes, cold, fear — as things only their owner has direct access to. You feel your own want; you can only observe someone else's. Saying ×弟は行きたい ("my brother wants to go") claims to read his mind. The language blocks this and makes you mark that you are reporting from the outside. がる is that marker: it literally says "displays the appearance of wanting."
The form: たい-stem + がる
Take 〜たい, drop the final い, and add がる: 行きたい → 行きたがる, 食べたい → 食べたがる. The result is a brand-new godan (う-) verb ending in る, and it conjugates like any other godan る-verb — not like an adjective.
| Form | Example | Meaning |
|---|---|---|
| Dictionary | 行きたがる | wants to go (habitually / generally) |
| Negative | 行きたがらない | doesn't want to go |
| Past | 行きたがった | wanted to go |
| Progressive | 行きたがっている | wants to go (right now) |
Because it is a normal verb, all the usual verb machinery applies — 〜ます, 〜て, 〜た — and nothing about it inflects like an い-adjective. This is the clean structural break from たい: たい is an adjective, たがる is a verb.
たがる vs たがっている: general tendency vs right now
This distinction trips up learners more than the form itself. Plain 〜たがる describes a habitual or general tendency — this is what such a person is always like. The progressive 〜たがっている describes a specific person's want at a specific moment. For a particular someone wanting something now, natural Japanese overwhelmingly prefers the progressive.
子供はみんな、お菓子を食べたがる。
kodomo wa minna, okashi o tabetagaru
All kids want to eat sweets. (a general truth)
弟は今、早く帰りたがっている。
otōto wa ima, hayaku kaeritagatte iru
My brother wants to go home early right now. (this moment)
うちの猫は、いつも外に出たがっている。
uchi no neko wa, itsumo soto ni detagatte iru
Our cat is always wanting to go outside.
彼は帰りたがっていますよ。
kare wa kaeritagatte imasu yo
He wants to leave, you know. (observed, right now)
Reach for bare 行きたがる to describe a momentary individual want and it sounds oddly generic — like reporting a permanent character trait. When in doubt about one person here-and-now, use 〜たがっている.
The object goes back to を
Recall that under 〜たい the object could take が for emphasis (水が飲みたい). Under 〜たがる that option disappears: because がる has fully verbed the expression, the object reverts to plain を. There is no ×お菓子が食べたがる.
子供がお菓子を食べたがる。
kodomo ga okashi o tabetagaru
The child wants to eat sweets.
みんな新しいゲームをやりたがる。
minna atarashii gēmu o yaritagaru
Everyone wants to play the new game.
娘はどうしても、あの人形を買いたがっている。
musume wa dōshitemo, ano ningyō o kaitagatte iru
My daughter wants to buy that doll no matter what.
がる is a whole family, not a one-off
The real prize here is seeing that がる is a general evidential suffix, not something glued only to たい. It attaches to a range of feeling-words that are otherwise restricted to the first person, and each time it does the same job: turn "I feel X" into "they act as if they feel X."
| 1st-person feeling |
| Meaning |
|---|---|---|
| 寒い (I'm cold) | 寒がる | (someone) acts cold, seems cold |
| 怖い (I'm scared) | 怖がる | (someone) is afraid of, gets scared |
| 痛い (it hurts me) | 痛がる | (someone) acts as if in pain |
| ほしい (I want it) | ほしがる | (someone) wants (a thing) |
| 〜たい (I want to…) | 〜たがる | (someone) wants to (do) |
子供が寒がっているから、上着を着せよう。
kodomo ga samugatte iru kara, uwagi o kiseyō
The kid looks cold, so let's put a jacket on them.
うちの犬は、雷を怖がる。
uchi no inu wa, kaminari o kowagaru
Our dog is afraid of thunder.
Once you see 寒い→寒がる and ほしい→ほしがる, 〜たい→〜たがる stops being an isolated rule and becomes one instance of a single, elegant principle: Japanese won't let you narrate another mind from the inside, so it gives you がる to narrate it from the outside. (For wanting a thing — the ほしい side — see 〜をほしがる.)
A register caution: たがる can sound presumptuous
Here is a point many textbooks gloss over. 〜たがる carries a faint flavor of judging from the outside, and sometimes of insisting on / being set on something. That is fine for children, animals, or a general crowd, but aimed at a superior or someone you must be polite to, it can sound blunt or even impertinent — as if you are coolly cataloguing their desires. To report a boss's or teacher's wish neutrally, prefer hedged evidentials or a quote instead:
部長は早く帰りたいようです。
buchō wa hayaku kaeritai yō desu
The department head seems to want to go home early. (polite hedge — better than 帰りたがっている for a superior)
先生も参加したいとおっしゃっていました。
sensei mo sanka shitai to osshatte imashita
The teacher said she'd like to join too. (quoting — respectful)
There is no fully clean rule here — you have to feel the social distance. The safe heuristic: たがる for children, pets, and generic groups; ようだ / らしい / quotation for people you're being deferential to.
Common mistakes
❌ 弟は日本へ行きたい。
otōto wa nihon e ikitai
Incorrect for a third person — plain たい claims to read his mind. Use たがる or quote him.
✅ 弟は日本へ行きたがっている。
otōto wa nihon e ikitagatte iru
My brother wants to go to Japan.
❌ 私は早く帰りたがっている。
watashi wa hayaku kaeritagatte iru
Incorrect about yourself — がる is for observing others. For your own want, use plain たい.
✅ 私は早く帰りたい。
watashi wa hayaku kaeritai
I want to go home early.
❌ 子供がお菓子が食べたがる。
kodomo ga okashi ga tabetagaru
Incorrect — under たがる the object takes を, not が.
✅ 子供がお菓子を食べたがる。
kodomo ga okashi o tabetagaru
The child wants to eat sweets.
❌ 彼は今、帰りたがる。
kare wa ima, kaeritagaru
Off — bare たがる sounds like a general trait; for one person's want right now, use the progressive.
✅ 彼は今、帰りたがっている。
kare wa ima, kaeritagatte iru
He wants to go home right now.
Key takeaways
- 〜たがる = たい-stem + がる, reporting a third person's want to do something: 行きたい → 行きたがる.
- It is a godan る-verb, conjugating たがる / たがらない / たがった / たがっている — not like an い-adjective.
- Prefer the progressive 〜たがっている for a specific person's want right now; bare 〜たがる reads as a habitual tendency.
- The object reverts to を (お菓子を食べたがる), unlike focused たい's が.
- がる is a general evidential shared with 寒がる, 怖がる, 痛がる, ほしがる — it lifts the first-person restriction on feeling-words.
- Use it freely for children, animals, and groups; for superiors, soften to 〜たいようです or a quote to avoid sounding presumptuous.
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Start learning Japanese→Related Topics
- 〜たい: Expressing Your Own DesireN4 — How ます-stem + たい states the speaker's own wish to do something — why it inflects like an い-adjective, why it's essentially first-person, and the が/を object alternation English has no match for.
- 〜ほしがる: Reporting Another's Want of a ThingN4 — How Japanese reports that a third person wants a thing — ほしがる, the がる-verb counterpart of ほしい, which switches the wanted object from が to を and describes observable wanting rather than reading someone's mind.
- 〜がほしい: Wanting a ThingN4 — How noun + が + ほしい says you want a thing — why wanting is framed as an adjectival state, why the wanted thing takes が, and how it splits from 〜たい (want to do) and 〜てほしい (want someone to act).
- Choosing Among the Desire FormsN4 — A decision grid for the whole Japanese wanting system — たい, たがる, がほしい, てほしい, ほしがる — sorted along two axes at once: whose desire it is and what kind of thing is wanted.