는지 까먹다

forget what, forget how

An embedded question with "-는지" (what it was that…) under 까먹다, the everyday casual word for forgetting. The lines are all about losing track of some small detail: what I did two days ago, what I ordered, what the sky even looks like, what I was talking about, what goes into it. 까먹다 is chattier than 잊다 or 잊어버리다 and belongs in speech, which is where all of these come from. It also literally means "peel and eat", so context does the sorting.

Register: casual spoken