When a dog is disobedient, the owner can often eat in front of it and use its desire to eat food to train it.

Dogs belong to the phylum Chordata, the subphylum Vertebrates, the class Mammalia, the subclass Eutheria, the order Carnivora, the suborder Schizopoda, and the family Canidae.

Also known as "dog" in Chinese, dogs are distributed all over the world.

Dogs, horses, cattle, sheep, pigs, and chickens are collectively known as the “six traditional animals”.

Dogs were domesticated from wolves.

As early as the hunter-gatherer era, people have domesticated dogs as assistants in hunting.

Therefore, dogs are the earliest domestic animals domesticated by humans.