Expresses 'to make someone do something', 'to let someone do something', or 'to cause someone to do something'.
Group 1 Verbs: Change the last hiragana to ~せる, Group 2 Verbs: Remove ~る and add ~させる, Group 3 Verbs: する → させる, くる → こさせる
Long explanation:
The ~させる verb form is used to describe causing or allowing someone to do something. It can be translated as 'to make someone do something', 'to let someone do something', or 'to cause someone to do something' in English. The formation of the ~させる form depends on the verb it is attached to.