Formal:
* 我 (wǒ): This is the most common and formal way to say "me." It's used in most situations, especially when speaking to someone older or in a professional setting.
Informal:
* 我 (wǒ): This is also used informally, but can sometimes sound a bit too formal in casual settings.
* 我 (wǒ) 自己 (zìjǐ): This literally means "I myself" and is used to emphasize the person's own action or opinion.
* 俺 (ǎn): This is a very informal and dialectal way to say "me" and is mainly used in northern China.
For example:
* 我叫李明。 (Wǒ jiào Lǐ Míng.) I am called Li Ming.
* 我自己做饭。 (Wǒ zìjǐ zuò fàn.) I cook by myself.
* 俺去买菜了。 (ǎn qù mǎi cài le.) I'm going to buy groceries.
The choice of which to use depends on the situation and your relationship with the person you're speaking to.