1) He began to laugh.

他笑起来了。
2) She broke into a laugh.

她突然笑起来了。
3) The lady in the store began to laugh.

女店员笑了起来。
4) He burst into a fit of laughter.

他突然大笑起来。
5) He broke into a loud laugh.

他忽然大笑起来。
参考词条