你好吗? (nǐ hǎo ma?)
This is a polite and general way to inquire about someone's well-being.
Here are some other ways to ask "How are you?" in Mandarin, depending on the context and your relationship with the person:
* 你最近怎么样? (nǐ zuì jìn zěn me yàng?) - "How are you doing lately?" (More informal and used with friends or family)
* 身体好吗? (shēn tǐ hǎo ma?) - "Are you feeling well?" (Focuses on physical health)
* 一切都好? (yī qiè dōu hǎo?) - "Is everything okay?" (Indicates concern for overall well-being)
It's important to remember that the tone of voice and the situation will also influence how the question is perceived.