代かわりになる

expression, godan verb (-ru)

substitute for; stand in for; fill in for

Used when someone or something takes the place of another person or thing, often in a temporary or replacement role.

• 彼かれが病びょう気きなので、私わたしが代かわりになる。

  Since he is sick, I will fill in for him.

• この材ざい料りょうがなければ、別べつのもので代かわりになる。

  If we don't have this ingredient, something else can substitute for it.