I misheard this as "ignis rapide pontes delet," was marked correct, and reported it as an answer that should not have been accepted.
I've noticed wrong answers being accepted more often later in the course. Is that because fewer people get to the end to report problems?
How can the audio be made clearer without making it overly-easy? This sentence seems like a great example of needing to enunciate very clearly to distinguish singular vs. plural, but hyper-enunciation means the listener can get lazy . . .