Do you worry about the impression you are giving your children?

What I worry about most, is that my son will pick up on some of my bad habits. I don't curse, but there are a few words taht I am attempting to omit from my vocabulary before they enter his. (Like stupid, shut up etc.) He has become a copy cat recently. Also, I tend to be quite sarcastic, and Ive been trying to tone that down as well, as I would hate to hurt his feeligns.