A grammar pattern expressing doing an action in advance or maintaining a state.
When to use
preparation, state maintenance, completion emphasis
The nuance
Attach -(아/어) 두다 to a verb stem. It emphasizes a completed or prepared action and has two main meanings: 1) doing something in advance (preparation), 2) maintaining a state. For example, 문을 열어 두다 means 'leave the door open (prepared)', 불을 켜 두다 means 'keep the light on (state maintained)'.
