Ollie is a 6 years old, Black mouth cir/Mastiff/Pitbull/Akita mix. He knows sit, shake and lay down. And takes treats gently from our hands. He is aggressive with dogs out in public but he is good with our other dog in the household.  He would probably be fine with a new dog In their home, but would need time to adjust. And he's never been mean to children or adults. I feel he needs to be in a place where he can run around and burn his energy off.