The Causative (させる)

The causative is used to express “make” or “let” someone do something”. In fact, we’ve already met one way to form these expressions when 〜てもらう was introduced. As we saw, this structure was not entirely neutral—often implying that the speaker was grateful to the person performing the action.

The causative form introduced below lets us form a similar expression, but it is more neutral and closer in meaning to “make someone do”. Furthermore, depending on the context, it can also be used to mean “let someone do”. Let’s take a look at the verb conjugations.

Group 1

We change the u-ending syllable to an a-ending syllable and add せる. The only exception is う-ending verbs where the ending syllable changes to わ.

English	Dictionary	Causative
to go	行いく	行いかせる
to say	言いう	言いわせる
to drink	飲のむ	飲のませる
to go home	帰かえる	帰かえらせる

Group 2

For all group 2 verbs we remove the る and add させる.

English	Dictionary	Causative
to see	見みる	見みさせる
to leave	出でる	出でさせる
to exist	いる	いさせる
to borrow	借かりる	借かりさせる

Note, however, that some causative conjunctions are rarely used. 見みさせる, for example, means “to make see” but instead we would say “to show”, which is the verb 見みせる.

Group 3

English	Dictionary	Causative
to do	する	させる
to come	来くる	来こさせる

The required particle for the person who will be made to perform the action depends on whether the verb is transitive or intransitive. For transitive verbs we require the target particle.

息子むすこに部屋へやを掃除そうじさせる。

To make your son clean his room.

友達ともだちにタバコをやめさせる。

To make a friend quit smoking.

先生せんせいは私わたしに論文ろんぶんを書かかせた。

The teacher made me write an article.

For intransitive verbs, the agent of the action takes the object particle.

公園こうえんで子供こどもを遊あそばせる。

Let children play in the park.

先生せんせいは私わたしを立たたせた。

The teacher made me stand.

And for those verbs that can be both transitive and intransitive (e.g. to wait), the correct particle will depend on the sentence structure.

彼女かのじょを待またせる。

Make her wait.

応募者おうぼしゃに答こたえを待またせる。

Make the applicant wait for a reply.

Nor does the agent have to be a person. Certain verbs are effectively changed into transitive verbs by the causative. The intransitive verb “to finish” is probably the most common example.

仕事しごとを終おわらせる。

To finish the job [to make the job finish itself].

進展しんてんを加速かそくさせる。

To accelerate progress.

The causative can be confusing for learners because there is no explicit distinction between “make someone do” and “let someone do”—the meaning is determined by the context.

帰かえらせてください。

Please let me go home.

This is clearly a request and so “let” is the appropriate translation.

息子むすこに部屋へやを掃除そうじさせる。

To make your son clean his room.

It’s reasonable to assume your son wasn’t asking your permission to clean his room.

公園こうえんで子供こどもを遊あそばせる。

To let children play in the park.

Nor would forcing children to play in the park sound natural.

The te form of the causative with あげる and くれる can be used to avoid ambiguity.

公園こうえんで子供こどもを遊あそばせてあげる。

To let children play in the park.

お母かあさんは公園こうえんで遊あそばせてくれた。

My Mum let me play in the park.

Care also needs to be taken when deciding between the causative and 〜てもらう. Below the first example sentence is more natural as it is in the translation. The second sentence is still grammatically correct, but would not be used.

医者いしゃに皮疹ひしんを診みてもらう。

To have the doctor take a look at a rash.

医者いしゃに皮疹ひしんを診みさせる。

To make the doctor look at a rash.

Finally, in casual conversation the せて te form of the causative often gets transformed to して which is easier to pronounce.

帰かえらしてくれない？

Won’t you let me go home?

僕ぼくは言いわしてもらうと、その提案ていあんを実現じつげんするのが難むずかしいかと思おもいます。

If you don’t mind my saying [if you’ll let me say], I think that proposal is going to be difficult to put into effect.

We will see the combination of the te form of the causative and もらう later when honorifics are introduced.