Causative form (〜させる / 〜せる) "make / let someone do"

Someone makes or allows another person to do something.

The causative says that someone makes or lets another person do something: 食べる (eat) → 食べさせる (make/let someone eat). Whether it means "make" or "let" depends on the situation: a mother making a child eat vegetables is "make"; a parent allowing a child to play is "let". The person who is made to act takes に with transitive verbs (子供に野菜を食べさせる) and を with intransitive verbs (子供を学校へ行かせる).

Used by parents, teachers, bosses and organisations talking about what they have people do (学生に作文を書かせる). With 〜てください / 〜ていただけませんか it becomes the standard polite way to ask permission for yourself: 休ませてください (please let me rest). With 〜てあげる / 〜てくれる it leans toward "let".

• Group 1: ない-stem + せる: 書く→書かせる, 行く→行かせる, 待つ→待たせる, 飲む→飲ませる
• Group 2: ない-stem + させる: 食べる→食べさせる, 見る→見させる
• Group 3: する→させる, 来る→来させる (こさせる)
• Causee (person made to act): に with a transitive verb, を with an intransitive verb
• Conjugates as Group 2: 行かせます / 行かせない / 行かせた / 行かせて

1. 01

   母は私に部屋を掃除させました。

   はは は わたしに へやを そうじさせました。

   My mother made me clean the room.

   Transitive verb 掃除する: the causee 私 takes に.

2. 02

   先生は学生を立たせた。

   せんせいは がくせいを たたせた。

   The teacher made the students stand.

   Intransitive verb 立つ: the causee 学生 takes を.

3. 03

   子供に好きなことをさせてあげたい。

   こどもに すきな ことを させてあげたい。

   I want to let my child do what he likes.

   させてあげる: the "let" reading.

4. 04

   先生は学生に毎日日記を書かせています。

   せんせいは がくせいに まいにち にっきを かかせています。

   The teacher has the students write a diary every day.

   Group 1: 書く → 書かせる. The students (causee) take に because 書く is transitive.

5. 05

   妻を心配させたくないので、病気のことは言わなかった。

   つまを しんぱいさせたくないので、びょうきのことは いわなかった。

   I didn't want to worry my wife, so I didn't tell her about the illness.

   Causatives of emotion verbs (心配させる, 笑わせる, 泣かせる, 喜ばせる) take を on the person.

• 〜させてください

  The causative + てください asks permission for yourself: "please let me…". This lesson is the base form. Compare side by side

• Causative-passive 〜させられる

  Told from the other side: the person forced becomes the subject (私は母に野菜を食べさせられた). Compare side by side

• Passive 〜られる

  Passive = something is done to the subject; causative = the subject makes someone else act. Do not mix the endings れる and せる. Compare side by side

• ✗

  母は私を野菜を食べさせた。

  ✓

  母は私に野菜を食べさせた。

  Why

  With a transitive verb there is already an object with を (野菜を), so the causee must take に. Two を in one clause is not allowed.

• ✗

  先生は学生に立たせた。

  ✓

  先生は学生を立たせた。

  Why

  立つ is intransitive, so the causee takes を.

• ✗

  子供を病院へ行かさせた。

  ✓

  子供を病院へ行かせた。

  Why

  Group 1 verbs take せる, not させる. 行かさせる (さ入れ) is a common slip that the exam counts as wrong.

The causative is used downward (parent → child, boss → staff). For asking a superior to do something you use requests (〜ていただけませんか), never the causative. "Let" is often made explicit with あげる / くれる / もらう: 好きなだけ遊ばせてあげた (I let him play as much as he liked), 使わせてもらった (I was allowed to use it). Emotion verbs are very common in the causative: 笑わせる (make laugh), 泣かせる (make cry), 驚かせる (surprise), 安心させる (reassure).