ok i am tring to do homework please help

Size (extremely large and extremely small)Temperament (aggressive or docile)

MARKINGS. for example, the spots on a dalmatian (eyes and ears) or a uniform saddle on a beagle, whether or not a dog sports socks, etc.DISPOSITION is a big one.SIZE like someone mentioned.HAIR TEXTURE tight curls, long straight and smooth. . . . .TIGHT JOWLS for drooling or not drooling.EAR SHAPE to exaggerate pointed or long and lazy depending on the breed.lots of stuff. Whatever trait you like in a dog, you can selectively breed for it. Even slightly modifying the color of the coat can be tweaked thru selective breeding. All of this can easily be achieved by breeding an offspring to the sire or dam, but unfortunately too much of this can lead to deformities.