勤快 (qín kuài) is an adjective describing someone who is energetic, diligent, and eager to take initiative—especially in daily tasks like cleaning, cooking, or helping others. The first character 勤 means 'diligent' or 'industrious', emphasizing consistent effort; the second character 快 means 'quick' or 'prompt', highlighting speed and readiness. Together, they convey not just hard work but also cheerful, proactive engagement—someone who doesn’t wait to be asked and gets things done efficiently and willingly.

This word is commonly used to praise children, household members, or employees for their helpfulness and reliability. It carries a warm, positive connotation and often appears in family or workplace contexts. While it can describe physical activity, it’s more about attitude and willingness than sheer speed or strength. It’s rarely used for inanimate objects or abstract concepts—always tied to a person’s behavior and spirit.