一無所知

一无所知
yīwúsuǒzhī
(idiom) not knowing anything at all; completely ignorant

CEDICT

Entry Composition

1 一 yī
  1. one
  2. single
  3. a (article)
  4. as soon as
  5. entire; whole; all; throughout
  6. "one" radical in Chinese characters (Kangxi radical 1)
  7. also pr. yāo for greater clarity when spelling out numbers digit by digit
2 無 wú
  1. not to have
  2. no
  3. none
  4. not
  5. to lack
  6. un-
  7. -less
3 所知 suǒzhī
  1. known
  2. what one knows