I agree with most of what ^ he said.
I use alot of Knee's and Elbows because im a wrestler and i personally am not the best striker in the world lol, thats how i loose is going through a stand up fight.
Useing your elbows you dont actually throw your elbow, when your in a clinch or grappling you use your shoulders, pecks, and back muscles to throw elbows. The best way to learn is to do what they show tito doing so much. Having a Bag on the ground and just work different positions on it.
Knees are about the same i use my ass muscles and my opposite leg's calf to pop my whole body up while i just having my thigh locked and pulling back while doing so.
What is it that is going to be on your mind when you're on your death bed? Will it be the tedious years of 9 to 5, or the memory of some great acheivement. Maybe a moment you stood in glory to the applause of millions.