Burst out laughing:
To suddenly start laughing.
“Burst out laughing”，意思就是这个人 “突然大声地笑了起来，放声大笑”。
例句
When I saw the man walk into a lamppost, I burst out laughing. He didn’t see what was so funny!
当我看到那个男人撞上路灯柱的时候，我放声大笑。但他却没觉得有什么好笑的！
Everyone burst out laughing when they saw what I was wearing to the party.
当大家看到我的聚会着装时，都大笑起来。
At the circus, the audience always bursts out laughing when the clowns appear – but I don’t see what’s so funny!
在马戏团表演中，当小丑出现时，观众总是放声大笑。但我可不觉得有什么好笑的！
