Burst out laughing 突然大笑起来

burst 爆发；突发

laugh 笑

1. The baby burst out laughing when he saw the cat slip. 这个婴儿看到猫滑倒了，突然大笑起来。

2. The kids burst out laughing when the clown fell down on stage.孩子们看到小丑在台上摔倒以后，大笑了起来。

Burst into laughter

Laughter n.笑；笑声

3. He burst into laughter when he turned around and saw his “bride” .他转身看到他的“新娘”以后，大笑了起来。