In / On
1. Don't punch me in the back of my head. (How come this correct? How can it be 'in' the back of your head?)
2. Don't punch me on the back of my head. (How come I never hear anyone one use 'on'?)
Re: In / On
A fist goes into the skin. It leaves an indentation. (A bruise is the tell-tale sign of that.)
Originally Posted by jack
a punch on the back of the head means, on the surface:
a slap on the face.
a slap in the face.
An open hand (a slap) strikes on the surface of the face and it goes into the skin, so both "in" and "on" are used.
She hit/punched/slapped me on the arm. (on the surface of my arm)
She hit/punched/slapped me in the arm. (into the skin, muscle)
Speakers use both, and they don't seem to bother with the semantics. Either "in" or "on" will do when you're angry, shocked, etc.