When you 'cuff' someone, you are hitting (or hit) someone lightly. There is no great force with the hit and it shouldn't hurt them. A cuff is often a glancing blow. For instance, if I cuff someone on the head, it means I am giving them a slight blow that glances off their head, rather than a blow that hits fully. When you 'pummel' someone, you are hitting them repeatedly. It is usually with force, speed and is a series of many blows. The person getting 'pummelled' is getting hurt. There is intent to hurt, unlike a cuff which is a single light blow or hit. When you 'strike' someone, you hit them with a single blow. It may be done with force, or it may be a light blow.

Hi Ellie! Cuff is a part of our hands. Ex.: I hurt my cuff; Pummel is like a punch. Ex.: During the fight he pummel your opponent; Strike is like a political action. Ex.: Today we begin a hunger strike.