Dogs do not smile. This is actually a fake smile. From a scientific point of view, dogs do not have as complex muscle structure as human faces. A dog's smile is not actually a smile. For example, if a dog grins but is accompanied by panting, it means the dog is expressing anxiety and pain; if the dog grins accompanied by airplane ears, it means that when the dog is accused, it looks well-behaved but does not admit its fault in its heart.

Tip:

Different breeds of dogs give people different feelings of laughter. For example, Samoyeds are known as "smiling angels". No matter what they are doing, as long as they look at you with their necks crooked, it will make people think that they are smiling sweetly. Even if the pug with a wrinkled face smiles at you, you will feel that it has a deep hatred for you.