为 + Person (for someone's sake)

Doing it for them

• for为wèi + Person + Predicate = "for / on behalf of (someone)".
• for为wèieveryone大家dà jiāto serve服务fú wù = "serve everyone."
• This for为wèi (wèi) means "for the benefit of" — careful, not in order to为了wèi le ("in order to").

for为wèi + Person + Verb Phrase

• for为wèi names who benefits from the action.

we我们wǒ menfor为wèieveryone大家dà jiāserve服务fú wù。

• for为wèieveryone大家dà jiāto serve服务fú wù = "serve everyone."

Recap

Read the full reference: HSK 5 grammar — Prepositions.