不明就里 bù míng jiù lǐ

DEFINITIONS

  1. not to understand the situation
  2. unaware of the ins and outs

CHARACTERS

不 bù no, not; un-; negative prefix
明 míng bright, light, brilliant; clear
就 jiù just, simply; to come, go to; to approach, near
里 lǐ unit of distance; village; lane