This combo introduces the fourth and final punch: the uppercut. Stand with your right foot forward, arms on guard. Throw a right jab, a left cross punch, then a right uppercut (bend your elbow into your body, rotate your right hip and heel, and imagine punching up and under your opponent's chin). Next, quickly repeat the cover move from round two by twisting your upper body and elbows to your left, right, and left (quickly counting "1, 2, 3" as you do it). Return to start. That's one rep.
Repeat 10 times in a row as quickly as you can, and then switch your stance and do 10 reps on the other side.