How Many Words Can A Dog Learn?
Trained dogs can learn up to 165 words. Beyond basic words which could be learned even as puppies such as sit, stay, and lie down, you can teach your dogs more words with some training. Association is a useful tool when teaching new words. Dogs learn faster when the object you are identifying is in hand. Enforcing behavior with positive feedback such as petting them or giving them treats is a basic and indispensable training device. Calling out your dog's name alerts your dog that you're about to bring up some words or commands you have taught.
However, the jury is still out on whether dogs could actually understand words as a form of language or if they are simply reacting to unconscious actions people do when they say particular words. Dogs are one of the most sensitive to human nonverbal communication since they have been domesticated for at least 20,000 years.