When we try to ask someone's family name, we usually say “你姓什么？” (nǐ xìng shí me? )
However, in lots of formal situations (especially in business situation), we can use “贵姓” (guì xìng ) to show our respect to the other person.
“贵” means expensive by itself, but it also contains the meaning of "honorable" "noble".
例：
△ (you and your new classmate) -casual way of asking
You : 你姓什么？ (nǐ xìng shí me? )
Classmate: 我姓Liu。(wǒ xìng Liu)
△ (you and your client)
You: 请问您贵姓？(qǐng wèn nín guì xìng?) -polite way of asking
Client: 我姓Liu。(wǒ xìng Liu)
picture reference:
http://image.slidesharecdn.com/random-130302065918-phpapp02/95/-8-638.jpg?cb=1362207710
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If you are interested in learning Chinese, feel free to e-mail me: jennychinesetutor@gmail.com
- Jenny