我们走在树枝上时，它们咔嚓一声断了。

The twigs ___snapped as we walked on them.

她的跟腱在比赛中突然断裂了。

Her Achilles tendon ___snapped during the competition.

他不小心把铅笔咔嚓一声折成了两半。

He accidentally ___snapped the pencil in half.