Expressing "Want" in Japanese (～たい)

To express the desire “to want” we take the stem of the verb (i.e. the present polite form with ます cut off) and add たい. The verb now behaves like an i-adjective and conjugates in exactly the same manner.

Verb	Group	Dictionary	Stem	Want
to write	1	書かく	書かき〜	書かきたい
to read	1	読よむ	読よみ〜	読よみたい
to say	1	言いう	言いい〜	言いいたい
to see	2	見みる	見み〜	見みたい
to do	3	する	し〜	したい

Because we have effectively changed the verb into an i-adjective, we should use が instead of the object particle を.

ビールが飲のみたいです。

I want to drink beer.

それがしたかったですよ。

I wanted to do that.

That being said, you will often see the object particle used in both conversation and writing—as it was for the potential form of the verb.

景色けしきがとてもきれいですよね。写真しゃしんを撮とりたいです。

The scenery is incredibly beautiful, isn’t it? I want to take a picture.

残念ざんねんですね！一緒いっしょに行いきたかったです。

That’s a shame! I wanted to go together.

上司じょうしと出張しゅっちょうに行いきたくないです。

I don’t want to go on a business trip with my boss.

今夜こんや、六本木ろっぽんぎで遊あそびたいです。

I want to hang out in Roppongi tonight.

To say want with a noun (e.g. “I want water”) we use the i-adjective ほしい.

新あたらしい時計とけいが欲ほしいです。

I want a new watch.

飲のみ物ものが欲ほしい。

I want a drink.

However, using ほしい is very direct—a child would use it to say, “I want water” or “I want something to eat”. Consequently, it is not appropriate to use to order in a restaurant, for example. We will see more polite ways of asking for something later when honorifics are introduced.

A Critical Rule for Third Parties

It is extremely important to remember that both 〜たい and ほしい can only be used to express your own desires (first-person), or to ask a listener about theirs in a direct question (second-person). You cannot use them to state what a third person wants. For example, the following are incorrect in Japanese:

彼かれは水みずがほしいです。(✘)

彼女かのじょは行いきたいです。(✘)

Because you cannot know another person’s inner feelings with absolute certainty, you must use different grammar structures (meaning “it seems he wants” or “he says he wants”) which we will cover later (it is typically JLPT N4 grammar).