[laugh/scream/shout (etc.)] your head off
to laugh/scream/shout etc. very much and very loudly.
He laughed his head off when he read the letter.
英语词组固定搭配大全包含18674条英汉双解词组，基本涵盖了全部常用英文词组、短语的翻译及用法，是英语学习的有利工具。