Tired Dog

This is a play on words. "Ruff" sounds like "rough." So, the joke suggests the dog had a difficult night, which is why it's tired.

• Dog
• Night
• Animal
• Sleep
• Bed
• Rest

• When my dog starts to bark, he starts to get ruff.
• What do you call a dog that tells time? A watchdog.
• Why do dogs howl? Because that's the other contraction they know.
• What time do dogs wake up? At school is the time dogs wake up.