eki no kaidan de subette, korobisou ni narimashita.

I almost slipped and fell on the station stairs.

Breakdown of eki no kaidan de subette, korobisou ni narimashita.

• の: possessive case particle
• で: location particle
• 駅えき: station
• 〜て: connective form

Questions & Answers about eki no kaidan de subette, korobisou ni narimashita.

Why is 駅の階段 used here? What does の mean?

の links two nouns.

• 駅 = station
• 階段 = stairs
• 駅の階段 = the station’s stairs or the stairs at the station

In natural English, this is usually just the stairs at the station or the station stairs.
So の is not doing anything complicated here; it is simply connecting station and stairs.

What does で mean in 階段で?

Here, で marks the place where an action happens.

So:

• 階段で滑って = slipped on the stairs
• not to the stairs
• not from the stairs

A common comparison:

• で = where an action takes place
• に = destination, time, or existence, depending on the sentence

In this sentence, the action 滑って happened on the stairs, so で is the natural particle.

Why is 滑って in the て-form?