笑個不停的英文是 "Laughing all the time"。

Laughing uncontrollably

Keep laughing uncontrollably

一：笑個不停，英文常用語為 "keep laughing" 或 "continue to laugh"。
二：此種持續(xù)喜樂的狀態(tài)更精確的表述可能是 "cannot stop laughing" 或者 "be in a fit of laughter"。