Conjugating Verbs to Causative Form (〜させる)

    • Verb
    • Conjugation Form
    The causative form is a type of Japanese verb form that often ends in 〜させる. It gives the verb the meaning of "to cause someone or something to do something."

    What Is the Causative Form?

    Causative form 〜させる refers to verbs ending in either 〜させる or kana from the あ column + せる—this includes verbs like 食べさせる (to have/let someone eat), 飲ませる (to have/let someone drink), or 来させる (to have/let someone come). When you want to say someone (or something) caused someone (or something) else to do something, you conjugate a verb into this form.

    If you are looking for more details about its meanings and functions, check out our usage page on causative 〜させる.

    Now let's take a look at how to convert Japanese verbs to the causative させる form.

    Godan  → 会わせる
     → 立たせる
     → 写させる
    代わ → 代わらせる
     → 書かせる
     → 泳がせる
     → 死なせる
     → 学ばせる
     → 休ませる
    Ichidan 食べ → 食べさせる
    起き → 起きさせる
    閉じ → 閉じさせる
    Irregular 来るく  →  来させるこ   
    する → させる

    Godan Verbs

    For godan verbs, replace the ending vowel from the う column on the kana chart to its corresponding あ column kana and add せる. So if the original ending is む, the new ending will be 〜ませる. If it's つ, your new volitional ending will be 〜たせる. Let's try conjugating the verb 読む (to read) into its causative form (because we are causing you to read this page right now).

     + ま + せる = 読ませる

    Now what about 買う (to buy)? This one looks even easier because the verb itself ends with う, doesn't it? But making 買う into 買せる is actually incorrect. In this case, it becomes 買せる.

    ❌ 買 + あ + せる = 買あせる

    ⭕️ 買 + わ + せる = 買わせる

    Why is this? This is because all the verbs ending in 〜う used to end in 〜ふ in classical Japanese—hundreds of years ago. So the verb 買う in classical Japanese is 買, and it changes to 買はせる. Unlike modern Japanese, these ancient ふ and は sounds are pronounced as う and わ, just like the particle は is pronounced わ today. The modern 〜う ending verbs still conjugate the same as the classical 〜ふ ending verbs, so the causative form of 買 is actually 買わせる. For the same reasons, the causative form of 会 (to meet) is 会わせる and 縫 (to sew) is 縫わせる.

    Ichidan Verbs

    For ichidan verbs, just replace the 〜る ending with 〜させる. For example, 食べ (to eat) becomes 食べさせる.

    Irregular Verbs

    There are only two irregular verbs to remember. Not bad! The causative form of く  (to come) is 来させるこ   , and する (to do) becomes a totally-different-looking verb: させる.

    Conjugations of Causative Shorter Form (Verb Conjugation)

    Although many textbooks don't cover this, there is actually another set of conjugations to make verbs causative. The reason that isn't always covered is that the usage is limited to casual speech or dialects like Kansai-ben. Since the verb in this form ends in 〜さす or あ-column kana plus す, we call it the causative shorter form. In order to make this form, just replace the 〜せる of normal causative forms with す. Here is the chart so that you can compare it to the normal causative form.

    Godan  → 会わす
     → 立たす
     → 写さす
    代わ → 代わらす
     → 書かす
     → 泳がす
     → 死なす
     → 学ばす
     → 休ます
    Ichidan 食べ → 食べさす
    起き → 起きさす
    閉じ → 閉じさす
    Irregular 来るく  →  来さすこ  
    する → さす

    Although usage in this form is limited, you may still hear certain words used this way as some have settled into common use as independent 〜す-ending verbs—for example 泳がす (to let someone move around freely), 寝かす (to put someone to bed, to lay something down), or 沸かす (to boil water).