7 year old Welsh Terrier

I was a 7 year old Welsh Terrier who owned the house and my person, I was friendly and knew “sit” but was the ALPHA and sat when I wanted. I am 18 pounds and I would bark loudly at big dogs I saw on my leash during walks. Now I am an 8 year old Welsh Terrier who has respect for everything around me, including the big dogs, and I sit when I am told. I let the big dogs go by me while staying in a down position. I know hand commands, wait in a down position until I am told I can go to get my food, and stop in my tracks when told do so. You CAN teach older dogs many new tricks!