어 두다

Do it now and leave it that way

어 두다 does something and lets the result stand, usually for later use: 대답하는 법도 함께 기억해 두면 좋아요 'it's good to memorize the reply too, ready for when you need it', 내가 경은이한테 좀 전화 해둘게 'I'll go ahead and call Kyung-eun.' It also covers leaving something in a state — 언제까지 날 이렇게 묶어 둘 거냐? 'how long will you keep me tied up?' Its near twin -어 놓다 means almost the same; 두다 leans more toward keeping something in reserve.