Is the only reason to teach sign language to a dog if you think he/she is going deaf? No! When you use both verbal and visual commands, and teach the dog to resond to either one, then when you do use them together, it actually sends a stronger message, and the dog is more likely to respond. I teach all of my dogs these commands with both verbal and visual cues:
Sit
Down
Stay
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When I teach hearing dogs these commands, I teach them using verbal and visual cues together, then...