A man is walking his pet cat in the street .
A dog chases a cat down the street while a man chases after them both .
A man is walking his pet cat in the street.
A dog chases a cat down the street while a man chases after them both.
One cannot be walking and chasing at the same time. Chasing implies one is running, not walking.
One can not be walking and chasing at the same time . Chasing implies one is running , not walking .