started laughing
三个人都笑了起来，显然这是个老笑话。
All three of them laughed; clearly, it was an old joke.
他们笑了起来。
They burst out laughing.
我们谁都没被他骗过，于是全笑了起来。
None of us had been fooled by him, so we all burst out laughing.
卡恩笑了起来。
Kahn laughed.
几个邻居笑了起来。
A few neighbors laughed.
他给我们讲了一个有趣的故事，我们都笑了起来。
He told us an interesting story, and we all burst out laughing.