The verb 姓 (xìng) literally means "to be surnamed" or "to have the surname." You can use 姓 to tell someone your own surname, or that of someone else.
Structure
Giving One's Surname
Subject + 姓 + Surname
Examples
Wǒ xìnɡ Wánɡ.
我 姓 王。
我 姓 王。
My last name is Wang.
Asking Someone's Surname
You can also use 姓 to ask people their surnames. You could do this quite directly by saying:
Nǐ xìnɡ shénme ?
你 姓 什么 ?
你 姓 什么 ?
What is your last name?
However, the polite way to ask has a set form:
Nín ɡuì xìn?
您 贵 姓 ?
您 贵 姓 ?
Literally this means "What is your honourable surname?" Use this form to be polite when asking people their surnames.
What is your honourable surname?