Re: Taking a punch...
Conditioning is vital. Everything - including taking a good shot - is harder when you're tired.
Taking a good punch is also a matter of seeing the shot, or anticipating it.
I always found the hardest punches to take, or more correctly, the punches that hurt me the most were hooks to the point of the chin, especially if you didn't see it coming.
Flush punches to the face will bloody your nose and make your eyes water, but they don't really hurt that much. Neither do punches to the side of the head.
But boy...you get caught on the point of the chin with a good hook and you'll know you're hit. Your lower jaw feels like it's going to get wrenched from your head.