Relaxation and concentration?
Johnny and his father are observing a couple of dogs screwing each other.
"Dad, what`re the dogs doing?" asks Johnny.
"Well, the one below has relaxed and the one above has concentrated."
"Okay, I`ve understood."
"What`ve you understood!?" asks the father sarcastically.
"Never relax in your life, dad, or you`ll get fucked like a dog!"
