구사해요 · 구사했어요 · 구사할 거예요 · 구사하세요
to use skillfully, to command (a language or technique)
Example
그녀는 영어와 중국어를 자유롭게 구사합니다.
She speaks English and Chinese fluently.
Word parts
구 drive+사 employ
Literally 'drive and employ': wielding a skill as if commanding it.