do in
phr. v..phr. v.. to make someone feel extremely tired or to kill someone; it can also mean to damage something badly.
phr. v.. to exhaust or fatigue someone; in a different register, to murder or kill; also used to describe damaging or ruining an object or body part.
That long walk really did me in.
He didn't realize that lifting those heavy boxes would do his back in for the rest of the week.
The detective suspected that the rival gang had finally decided to do him in over the unpaid debt.
highly informal; the 'exhaust' sense is common in daily speech, while the 'kill' sense is often found in crime fiction.
focus on the 'exhaust' sense for general learners, but mention the 'kill' sense as a common trope in movies and books to avoid confusion.
The workout did in me.The workout did me in.when using a pronoun like 'me' or 'him', it must go between 'do' and 'in'.