Breakdown of geu sungan jeonghwa hwaldongi sijakdoeeossseupnida.
Questions & Answers about geu sungan jeonghwa hwaldongi sijakdoeeossseupnida.
그 순간 literally means that moment, but in a sentence like this it usually works adverbially: at that moment or then.
Korean time expressions often appear without a particle when they are being used as adverbs of time. So:
- 그 순간 정화 활동이 시작되었습니다. = At that moment, the cleanup activity began.
You can also say 그 순간에, and that is grammatically fine, but leaving off 에 is very common and natural.
이 is the subject marker.
Here, 정화 활동이 means the cleanup activity is the thing that began. So the activity is the subject of 시작되었습니다.
- 정화 활동이 시작되었습니다. = The cleanup activity began.
If you changed it to 정화 활동은, the meaning would still be possible, but the nuance would shift more toward making 정화 activity the topic, as in As for the cleanup activity, it began.