Korean phrase
언제부터 ~했어요? eon je bu teo ~ hae sseo yo
Meaning
Since when have you been ___?
When to use it
This asks when a continuing activity started. It is a polite, everyday question about how long the activity has continued.
Example dialogue
언제부터 한국어를 공부 했어요? eon je bu teo han gu geo reul kong bu hae sseo yo
Since when have you been studying Korean?
작년 가을부터 매일 조금씩 공부하고 있어요. chang nyeon ka eul bu teo mae il cho geum ssik kong bu ha go i sseo yo
I've been studying a little every day since last fall.