James Williams Sensei of Nami-ryu Aiki Heiho presents one-two, jab-punch combinations, the bread and butter of striking with the hands.
During this drill, pay attention to Williams Sensei's previous lessons: Stance, head movement, footwork, etc.
You are always programming. Fundamentals are more important than speed at first.
You will fight like you train so pay attention and don't get caught up in just working out or trying to hit the bag hard.