一知半解很危險。

A little learning is a dangerous thing.

Source: Tatoeba

Sentence Composition

1 一知半解 yīzhībànjiě (idiom) to have a superficial knowledge of a subject; to know a smattering of sth
2 很 hěn
  1. very; quite
  2. (also, often used before an adjective without intensifying its meaning, i.e. as a meaningless syntactic element)
3 危險 wēixiǎn
  1. danger
  2. dangerous