My Jack Russell is persistently snapping at me?

pay attention to your body lauange around him,dont look himm in the eyes,and keep your head low around him(to sumbit to him). and if you and to assert your dominance to him, you need to act like a dog yourself. bare your teeth at him and growl.and if he still trys to bite you,bite right back! hope it helps! it may go away in a while though,yaknow he will stop. (i think its breeding season mabey)