頭懸梁，錐刺股 [头悬－－锥－－]

Jyutping tau4 jyun4 loeng4 , zeoi1 ci3 gu2
Pinyin tóu xuán liáng , zhuī cì gǔ

Definitions (CC-CEDICT)
  1. lit. with his head attached to a beam and stabbing his thigh with an awl (idiom)
  2. fig. to study assiduously and tirelessly