bi on nareneun hyeongwan badageul jaju sseureoya hae.

object particle

Breakdown of bi on nareneun hyeongwan badageul jaju sseureoya hae.

• ~는: topic particle
• 자주: often
• ~에: time particle

Questions & Answers about bi on nareneun hyeongwan badageul jaju sseureoya hae.

Why is it 비 온 날 and not 비 오는 날?

Both are possible, but they are slightly different.

• 비 오는 날 = a day when it is raining / a rainy day
• 비 온 날 = a day when it rained

In real life, 비 온 날 often suggests that rain has fallen and, as a result, the entrance floor is dirty or wet. That matches this sentence well, because tracked-in water or dirt is the reason you need to sweep.

So the sentence is focusing a bit more on the result of the rain than just the weather description.

Shouldn't it be 비가 온 날? Why is 가 missing?

비가 온 날 is also correct. In Korean, particles are often omitted when the meaning is still clear, especially in common expressions.

So these are both natural:

• 비가 온 날에는 ...
• 비 온 날에는 ...

The shorter version sounds very natural in everyday Korean. This kind of omission happens a lot, especially with weather expressions like 비 오다.

What does -에는 mean in 날에는?