They understand intonation, but words? Huh uh.
Um... when I say the word “bath’ to my dog... she sometimes hides under the table. LOL
BS, I can talk to my dog in regular tone i.e. commands, she understands all of them. She can also here me put on my socks and shoes from the other end of the house. She understands when I say she has to stay home and watch the house in a normal conversational tone of voice, she gets a sad face but she understands,
They have to understand the words which requires learning definitions by experience. Of course they don’t understand words at first hearing.
Different dogs have different vocabularies. I had a black lab that had about 20 words which he clearly understood. Those words he could understand regardless of how you said them. He even learned that G.O. and W.A.L.K. meant that I was about to go or walk. Anything else was all about intonation.
My current mutt can pick out about 3-4 words. She is dumb but sweet.
Personally, I have observed clear indications of a rather developed sense of humor in both species--as I am sure have a great many others.
Trained dogs understand the meaning of command words (command words are given in the same tone). Imported dogs respond to commands in the language they know. They have to relearn the commands in a new language.
Some dogs can understand conversations (perhaps imperfectly) and respond accordingly.
Once my client and I were talking about her dog and she informed me that the dog barked too much “when there’s a strange dog in the backyard”. Her dog came flying into the room, leaped at the window and started barking loudly while looking around. There was no dog in the back yard.