Expressing Desire with the たい-Form

What is the たい-Form

The たい-form (tai-form) is a verb conjugation used to express a desire to do an action. In English, this translates to "want to [verb]."

When you attach たい to a verb, the verb grammatically transforms into an I-adjective. This means that once a verb is in the たい-form, you conjugate it exactly the same way you would conjugate a regular I-adjective. For a refresher on how I-adjectives work, see Introduction to Japanese Adjectives.

It is important to note that the たい-form is generally only used to describe your own desires ("I want to...") or to ask direct questions about the listener's desires ("Do you want to...?").

Conjugating the たい-Form

To create the たい-form, you must first find the verb stem. This is the same stem used for the polite "ます" (masu) form. You simply take the stem and add たい.

1. Ru-Verbs (Ichidan)

For verbs ending in , simply drop the and attach .

2. U-Verbs (Godan)

For verbs ending in an "u" sound, change the final "u" vowel to the corresponding "i" vowel from the same consonant row, then add .

3. Irregular Verbs

There are only two main irregular verbs to remember for this form. Their stems change as follows:

Particles with the たい-Form

When a verb normally takes the direct object particle , you have the option to change it to the subject particle when using the たい-form.

Both are grammatically correct and widely used in modern Japanese. Using slightly emphasizes the object you desire, whereas puts equal focus on the action itself. For a broader overview of particle usage, refer to Introduction to Japanese Particles.

Note that this optional change only applies to . Other particles like , , or remain exactly the same.

Tenses and Politeness

Because the たい-form turns a verb into an I-adjective, you conjugate it just like one to express negative desires ("don't want to") or past desires ("wanted to").

To make it polite, simply add at the end. For casual speech, omit the . See Introduction to Japanese Tenses for more details on general tense conjugation.

Here is how the verb looks across different tenses in the polite form:

ほしい vs たい

A common point of confusion is when to use versus .

• Use when you want to do an action (used with verbs).
• Use when you want a physical object or thing (used with nouns).

Study Tips

The たい-form is straightforward because it behaves predictably like an adjective once formed. As you continue to read and listen through A Practical Guide to Language Immersion, you will encounter this form frequently, and its usage will quickly become second nature.

A useful combination to look out for is using the Connect ideas with the て-Form followed by みたい (the tai-form of ). This translates to "want to try doing [verb]."

You might also notice that Japanese speakers rarely use the たい-form directly to state what a third person (he, she, they) wants to do. Saying sounds slightly unnatural because it assumes you know exactly what is in someone else's mind. Instead, speakers use grammar structures that imply "appears to want" or "said they want." You do not need to worry about the specifics of these third-party grammar rules immediately; simply being aware of this distinction will help you notice it during immersion.