From Korean Wiki Project
Verb + 는 대신 : This is used when the speaker wants to replace or substitute an action for another action. This can be translated as "instead of (verb)ing."
|Rule 1:||If there is no 받침 or if the adj/verb stem ends with a ㄹ 받침|
|Rule 2:||If there is a 받침 at the end of the adj/verb stem|
|공부하는 대신 게임했다.||Instead of studying, I played games.|
- Special pronunciation rule?