Dogs are so smart.

They have an instinctual knowledge of context (e.g., bite sleeves).

Here's another example:

In their world, showing teeth is a sign of warning/aggression; while they know that when humans smile, the human is probably a kind dog lover. Tails immediately go for a spin...

Unfortunately, most humans can't do this. Like when a dog's ears are back. A lot of people don't know that It could mean affectionate submission or a prelude for attack/defense.

Namaste, JaiChai