They both laughed exuberantly.

他俩都活力四射地大笑起来。

《柯林斯英汉双解大词典》

They both laughed but it was not because the idea was laughable but because they both so liked it.

他们都笑了，但这并不是因为这个想法很可笑，而是因为他们都很喜欢它。

youdao

"So are you," said Mary, and they both laughed.

“你也是。”玛丽说，两人都笑了。

youdao

When I asked them how they did it, they both laughed and told me that it wasn't always an easy road.

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When asked about the apparent contradiction between being trustworthy enough to operate on a human brain but not trustworthy enough to drive, they both laughed, shrugged and began to discuss their expectations for life after they are actually are neurosurgeons.

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