Formal:
* 男士 (nán shì): This is the most general and formal term for "man" or "gentleman."
Informal:
* 小伙子 (xiǎo huǒ zi): This is a common and informal way to refer to a young man, often used for someone who is friendly and approachable.
* 男人 (nán rén): This is the most direct translation of "man," but it can sometimes sound a bit blunt in casual conversation.
* 哥们儿 (gē menr): This is a very informal and friendly term for "buddy" or "friend," often used between close friends.
Other options:
* 家伙 (jiā huo): This is a more informal and casual way to refer to a person, but it can also be used in a negative or dismissive way.
* 人 (rén): This is a very general term for "person" and can be used in place of "guy" in some cases.
Example:
"The guy is over there." could be translated as:
* 那个男士在那边。(Nà ge nán shì zài nà biān.)
* 那个小伙子在那边。(Nà ge xiǎo huǒ zi zài nà biān.)
* 那个家伙在那边。(Nà ge jiā huo zài nà biān.)
The best translation will depend on the specific context and your intended meaning.