埃伦忽然大笑起来。

Ellen pealed with laughter.

《牛津词典》

她忽然哈哈大笑起来。

She burst into peals of laughter.

《牛津词典》

他还想再说下去，可是这两个年轻人忽然一齐大笑起来：我的轻浮的小姐很高兴地发现她可以把他的奇怪的话当作笑料了。

He was about to enlarge further, but the two youngsters broke into a noisy fit of merriment; my giddy miss being delighted to discover that she might turn his strange talk to matter of amusement.

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