hammer (something) into (one's/someone's) head(redirected from hammer it into his head)
hammer (something) into (one's/someone's) head
To commit some piece of information into one's or someone else's long-term memory, especially through intense repetition. How many times do I have to hammer it into your head? Do not drive my car unless I give you permission first! I've just been trying to hammer these formulas into my head for the big test tomorrow!