반짝

in a flash

Explanation

1. in a flash
A word describing a small light appearing shortly and soon disappearing.

2. soberly
A word describing one pulling oneself together instantly.

3. suddenly
A word describing a thought suddenly striking one's mind.

4. like a flash
A word describing an object, person, incident, etc., appearing shortly and soon disappearing.

5. interestingly
A word describing a certain remark suddenly catching one's attention.

6. clearly
A word describing something being clearly seen instantly.

7. without a wink
A word describing one staying up, not sleeping.