put your foot down
US /pʊt jʊər fʊt daʊn/
UK /pʊt jʊər fʊt daʊn/

1.
단호하게 나서다, 강경하게 대처하다
to use your authority to stop something happening
:
•
My parents finally had to put their foot down and tell me I couldn't go to the party.
부모님은 결국 단호하게 나서서 파티에 갈 수 없다고 말씀하셨다.
•
The teacher had to put her foot down about the excessive talking in class.
선생님은 수업 중 지나친 잡담에 대해 단호하게 대처해야 했다.