What dogs hear when you talk to them
Talk to a dog long enough and you start to wonder what is actually getting through. The answer from research is delightfully lopsided: far fewer words than we imagine, and far more than the words.
The words part
A trained pet dog reliably knows a handful of words; exceptional ones, like the border collie Chaser, learned over a thousand object names. But your average dog's vocabulary sits somewhere between twenty and a hundred, and most of it is proper nouns of their life: walk, dinner, the names of family members, the forbidden shoe.
Here is the part most owners miss: dogs do not parse grammar. Sit down, sit here, would you sit, sit, and down, all collapse into whichever sound pattern they have learned to bet on. Consistency of sound beats correctness of grammar every time. A dog trained on a word in one language will ignore your flawless translation of it.
The everything-else part
The bigger channel is not the words. Tone carries first: dogs separate cheerful from neutral from low and serious without any training at all. Brain imaging work found that dogs process familiar words and emotional tone in separate hemispheres, and they combine the two. Meaning arrives as tone plus word, and mismatches confuse them. A bright voice saying bad dog produces a visibly torn animal.
Around the voice sits everything else: your posture, your pace, the smell of stress, the length of your sigh. Anyone who has tried to fake cheerfulness at a nervous dog knows the audit runs deep.
What to actually do
Pick one sound per concept, short and distinct, and defend it like a password. Keep your tone matched to your meaning. Talk as much as you like; dogs appear to enjoy the channel being open even when the content is beyond them. Narrating your day to a dog is a fine thing to do, and there is no evidence it hurts, and much that the dog likes the ritual of it.
The famous finding that dogs process speech asymmetrically, familiar words to one ear, emotional charge to the other, matches what owners have always sensed. The dog is not listening to your sentences. It is listening to you. The sentence just rides along.