In China, while asking women's age is becoming less common nowadays, traditionally, people don't usually mind too much about asking one's age. Nevertheless, Chinese pay attention to how you ask about age for different age groups. "你几岁了？(Nì jǐ suì le)" is usually used to ask a child who is below 10 years old. "你多大了？(Nǐ duō da le)" is usually used to ask a teenager. "您多大岁数了？(Nǐn duō dà suì shù le)" is usually used to ask middle-aged and elderly people. 
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