Hello The expression you are looking for is '수고했어요' 수고- means hard work, trouble or effort (however it's not commonly used on its own) 했어요- did So you have worked hard or you did work hard is 수고했어요 or also could say 수고하셨습니다 to be even more polite This is a fixed expression and is commonly used, however do not use it with people much older than you as it could seem to be rude Hope this helps^^