다 두다

put something somewhere and leave it

-에다(가) marks where a thing is put, and 갖다 두다 is taking it there and leaving it: 집에다 갖다두면 'if you take one of these home and stick it there', 도시에 갖다 둬 'put it in a city'. The question form asks where something was left — 내 가방 얻다 두고 왔지?, 'where did I leave my bag?', where 얻다 is 어디에다 squeezed short. 갖다 놓다, in the last line, means the same thing.

Register: everyday spoken