jump the shark
(usually of television shows) to reach a point where something stops becoming more popular or starts to decrease in quality:
The show jumped the shark a few years ago.
Will Twitter soon jump the shark?
英语词典包含110679条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。