Between

가운데에

gaunde-e

(in the position or interval that separates two things)

간에

gan-e

(in the position or interval that separates two things)

간을

gan-eul

(in transit from one to the other)

끼리

-kkiri

(shared in confidence by)

사이

sai

(one of, representing a choice)

사이에

sai-e

(in the position or interval that separates two things)

중 하나

jung

(one of, representing a choice)