Keep your nose to the grindstone.
More Danish Proverbs:
Hair by hair and the head gets bald.Danish
Too many captains will sink the ship.
Danish
A headstrong man and a fool may wear the same cap.
Danish
He who spends more than he should Shall not have to spend when he would.
Danish
Better a daughter that has been slept on than a son who has been hanged.
Danish
A child's back must be bent early.
Danish