Grammar
N4 verb-grammar

Do a favor 〜てあげる / 〜てやる

Meaning

I (or someone on my side) do a favor FOR someone else. The direction of action is OUTWARD from me. てやる is the casual/blunt form (toward equals/inferiors, or for plants/animals).

Formation

Notes

WARNING: using てあげる directly TO a superior sounds condescending ("I'll do you a favor"). In formal speech, use humble 〜てさしあげる, or better, rephrase with 〜ましょうか. Politer: 〜てあげます.

Examples

I carried my friend's luggage for them.

Breakdown
I (topic) friend (modifier) luggage (object) carried for

Shall I tell you the way?

Breakdown
way (object) tell (te) shall I do for

I read a book to my little sister. (てやる = toward inferior/equal)

Breakdown
I (topic) younger sister to book (object) read (te) did for

Please water the flowers. (てやる for plants/animals)

Breakdown
flower to water (object) give (te) please

I bought him a present for his birthday.

Breakdown
birthday on present (object) bought for

⚠️ Often confused with

Receive a favor 〜てくれる / 〜てくださる

Someone ELSE does a favor FOR ME (or my in-group). The direction of action is INWARD to me...

Get someone to do 〜てもらう / 〜ていただく

I GET/RECEIVE someone else to do something (for me). Focuses on the receiver (me) actively...

I want you to 〜てほしい

Expresses the speaker's desire for SOMEONE ELSE to do something — "I want you to ~". The d...

Could you please 〜ていただけませんか

A very polite request — "could you please ~ for me?". Built from humble いただく / もらう...