For example, they dig. Digging is an inherent trait in Rat Terriers and they will spend a great deal of time digging in your yard and garden in an urgent quest to reach China by nightfall.
Don’t despair. Give him one area in the yard to dig up to his heart’s content and he’ll be fine.
A Rat Terrier has lots of energy; you should be able to spend at least 40 minutes a day exercising your dog.