The causative form is used to describe that someone has let, had, or made someone else do something.

The causative form is constructed by adding (さ)せる [(sa)seru] to the mizenkei. The mizenkei + せる (seru) is used with Group 4 (or yodan katsuyou) verbs, and the mizenkei + させる (saseru) is used with Group 2 (or nidan katsuyou) verbs.

Irregular verbs

The causative form of 来る (kuru) is formed by placing させる (saseru) after the mizenkei. The causative form of する (suru) is formed by placing せる (seru) after さ (sa).

RentaikeiMizenkei + (さ)せる [(sa)seru]
買う kau買わせる kawaseru
書く kaku書かせる kakaseru
出す dasu出させる dasaseru
待つ matsu待たせる mataseru
食べる taberu食べさせる tabesaseru
見る miru見させる misaseru
する suruさせる saseru
来る kuru来させる kosaseru


When adding (さ)せる [(sa)seru], a Group 2 verb, to the mizenkei the resulting verb is also conjugated as Group 2 verbs.

The grammatical construction

The causative form is used to describe that “A” makes “B” do “C”. “A”, is then followed by the particle に (ni), “B”, who performs the actual action, is followed by the subject particle が (ga), and “C” is followed by the object particle を (wo).

“A”が”B”に”C”をさせる。
“A” ga “B” ni “C” wo saseru.

私が友達に宿題をチェックさせた。
Watashi ga tomodachi ni shukudai wo chekku saseta.
I had my friend check my homework.
I let my friend check my homework.