keep your nose to the grindstone
US /kiːp jʊər noʊz tə ðə ˈɡraɪndˌstoʊn/
UK /kiːp jʊər noʊz tə ðə ˈɡraɪndˌstoʊn/

1.
travailler d'arrache-pied, bosser dur
to work hard and continuously at a task
:
•
If you want to succeed, you need to keep your nose to the grindstone.
Si tu veux réussir, tu dois travailler d'arrache-pied.
•
She's been keeping her nose to the grindstone all semester to get good grades.
Elle a travaillé d'arrache-pied tout le semestre pour obtenir de bonnes notes.