Japanese Causative Form: Guide on Causative and Causative-Passive Forms With Particles

Ever get confused by Japanese causative form when learning Japanese? You're definitely not alone. The causative form trips up pretty much everyone. You're dealing with させる (saseru) endings, particles that seem to change randomly, and the whole "make versus let" distinction that doesn't always translate cleanly from English. I'm going to break down exactly how the causative form works, how to conjugate it properly, and when to use which particles. We'll cover the causative-passive too, because that combination confuses everyone at first.

What the Japanese causative form does

In Japanese, both of these meanings use the same grammatical structure, which feels weird at first if you're coming from English.

When you see a verb like (tabesaseru), it means "to make/let someone eat." The context tells you whether it's forced or permitted. If a parent says (kodomo ni yasai wo tabesaseru), they're probably making their kid eat vegetables. If someone says (tomodachi ni keeki wo tabesaseru), they're likely letting their friend eat cake.

The causative form transforms any verb into a transitive verb that requires a subject (The person causing the action) and an object (The person performing the action). This is why particles matter so much with causatives.

How to conjugate the causative form

Let me walk you through conjugating verbs into the causative form. The process differs depending on whether you're working with a godan verb, ichidan verb, or irregular verb.

Godan verbs (う-verbs)

For godan verbs, you change the final う (u) sound to the あ (a) sound in the same consonant row, then add せる (seru).

Here are more examples:

Ichidan verbs (る-verbs)

Ichidan verbs follow a simpler pattern. You drop the る (ru) and add させる (saseru).

Examples:

Irregular verbs

Japanese has two main irregular verbs: する (suru) "to do" and (kuru) "to come."

The conjugation patterns stay consistent across all verb types, which is pretty cool once you get the hang of it.

Particles: に versus を

This is where things get interesting. The particle you use with causative verbs depends on whether the original verb is transitive or intransitive.

Intransitive verbs + に

When the original verb is intransitive (Doesn't take a direct object), you use に (ni) to mark the person you're making or letting do something.

The verb (iku) is intransitive. You say:
。
The teacher made the student go to the library.

The student is marked with に (ni) because (iku) doesn't normally take a direct object.

Transitive verbs + を

When the original verb is transitive (Takes a direct object), you typically use を (wo) to mark the person doing the action.

The verb (taberu) is transitive. You say:
。
The mother made the child eat vegetables.

Wait, that has two を (wo) particles, which feels awkward. In practice, Japanese speakers often switch the person marker to に (ni) to avoid the double を (wo):
。

Both versions are grammatically acceptable, but the に (ni) version sounds more natural.

The real pattern: に is used more often

Here's what actually happens in daily Japanese: に (ni) gets used way more often than を (wo) with causative verbs, regardless of whether the original verb is transitive or intransitive. The に (ni) particle just sounds better and avoids confusion.

You'll hear both, but に (ni) dominates in conversation. If you stick with に (ni) for the person and を (wo) for the object (If there is one), you'll sound natural most of the time.

Causative-passive form: The double whammy

The causative-passive form combines the causative with the passive form. This expresses being made to do something or being forced to do something. It's the ultimate "I didn't want to do this" grammatical structure.

To form the causative-passive, you first make the verb causative, then conjugate that causative verb into passive form.

The verb (kaku) "to write" becomes:

Both mean "to be made to write." The shortened version sounds less clunky and gets used more in conversation.

Example sentence:

The causative-passive form always implies some level of unwillingness or inconvenience. You wouldn't use it for something you wanted to do anyway.

For the causative-passive abbreviation for る-verbs, does the さ count as both the あ sound from the ない form and also as the replacement of せら? Kind of. The さ (sa) in される (sareru) represents the causative marker that merged with the passive ending. You're essentially compressing させられる (saserareru) by dropping the せら (sera) part and keeping just される (sareru). The あ (a) row sound is already there from the causative conjugation, so される (sareru) attaches directly to it.

Politeness levels with causative verbs

Causative verbs conjugate for politeness just like regular verbs. You add ます (masu) to make them polite.

The causative-passive also takes ます (masu):

Make or let someone: Reading context

Is this person making someone do something or letting them? You have to read the context. Japanese doesn't distinguish between "make" and "let" grammatically within the causative form itself.

This sentence, (kodomo wo asobaseru) could mean "make the child play" or "let the child play." If the parent is saying it while the kid wants to study, it's probably "make." If the kid has been begging to go outside, it's "let."

The surrounding context, tone, and situation tell you which meaning applies.

Sometimes the verb itself gives hints. (nakaseru) "to make someone cry" is almost always involuntary or negative. You're not "letting" someone cry in a permissive sense.

Common mistakes to watch out for

When you're learning causative conjugation, watch out for these common errors:

Practicing causative forms

If you want to practice spotting causative forms in real Japanese content, Migaku's browser extension and app let you look up any verb instantly while watching shows or reading articles. You can see the conjugation breakdown and save examples to review later. There's a 10-day free trial if you want to check it out.

FAQs

Immerse yourself in daily Japanese content to learn causative and passive forms

First time learning this grammar? Everything looks strange. Your listening reaction to the causative sentences is slow, let alone using them with correct verb forms and particles when speaking. However, as you expose yourself to more native Japanese content, you will be able to recognize verbs in their different grammatical forms instantly.

The dreary acquisition phase will come to an end.