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The most common criterion for measuring intelligence in dogs is how easy the dog is to train. Researchers look at how quickly the dog can figure out what the trainer is asking for, how likely the dog is to repeat the action, how many commands the dog can learn and how long it can retain a learned command without reinforcement. However, these results can be skewed by the different ways some breeds interact with people. The most intelligent breeds of dog are working breeds.

• Helpful indeed
• Most loving ones
• Outdoing the humans
• Little but not the least
• Testing IQ
• A true friend
• Distant relatives
• Becoming dangerous