手不释卷（手不釋卷）　

◎ 手不释卷 shǒubùshìjuàn

[be very studious;with a book always in hand] 卷:古代指抄写的卷帙,即书籍。手中一直拿着书籍片刻不放。形容勤勉好学或读书入迷