가는 말이 고와야오는 말이 곱다 (Ganeun mari gowayaoneun mari gopda). The literal meaning is
if the outgoing words are beautiful, then the incoming words will be beautiful too. That means if you expect somebody to be nice to you then you should be nice too. But you know..no matter what happen we have to be nice, right? It’s kinda hard since we have those days when we’re sensitive, but..We live not to be bad.
So..remembering that fact might help. Nice guys and girls rock 🙂