giggle|giggled|giggling

她在演讲期间紧张地咯咯笑了起来。

She ___giggled nervously during the speech.

别咯咯笑了！没那么好笑！

Stop ___giggling! It's not that funny!

那位老妇人像害羞的女学生一样咯咯地笑。

The old lady ___giggled like a shy schoolgirl.