은커녕

'Forget X — not even…'

-은커녕 knocks down one thing and then denies something even smaller: 게다가 상승은커녕 더 내려가고 있어 'forget going up — it's dropping further.' It always attaches to a noun, and the rest of the sentence has to supply the lesser thing that also failed: 하늘은커녕 아무것도 보이지 않는걸요 'never mind the sky, I can't see anything at all.' It is the standard way to express bitter disappointment about a gap between hope and reality.