You do something for someone or something else. This is for people or things below you. It is also for plants or animals.
Verb [て-form] + やるPrimary
You do something for someone or something else. This is for people or things below you. It is also for plants or animals.
毎日、うちの犬に餌をやってるよ。
I feed my dog every day.
弟の宿題を手伝ってやったのに、お礼も言われなかった。
Even though I helped my little brother with his homework, I wasn't even thanked.
あんな奴の頼みなんか、絶対に聞いてやらないぞ。
There's no way I'm going to grant a request from a guy like that!
「かかってこい！俺が相手になってやる！」
Bring it on! I'll be your opponent!'
枯れかけていた観葉植物に、栄養剤をやっておいた。
I gave some nutrients to the houseplant that was starting to wither.
This phrase can show many feelings. It can be like a gruff 'I'll do it for you' to a pet. It can also be angry, like 'I'll show you!' or 'So what?'. How it feels depends on the situation and how you say it.
This is different from "~te ageru". You use "~te yaru" for people below you. This includes pets or plants. Using it for someone equal or above you is very rude. "~te ageru" is for everyone else.
Don't use this when you talk to your boss. You use this for people or things below you. This means someone younger or lower in rank. It can be for animals or even things you don't respect.
Less formal alternatives(1)
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