牛角挂书

to study assiduously and tirelessly (idiom); see also 头悬梁，锥刺股

lit. with his head attached to a beam and stabbing his thigh with an awl (idiom); fig. to study assiduously and tirelessly

lit. to pierce the wall to steal a light (idiom); fig. to study diligently in the face of hardship

lit. always with a book in hand (idiom); fig. (of a student or scholar) diligent and hardworking

lit. the leather binding (of the bamboo scroll) has broken three times; fig. to study diligently

lit. to collect fireflies and study by their light (idiom); fig. ambitious student from impoverished background; burning the midnight oil