Learn Italian: Il ponte misterioso si sgretola e non ci passa mai nessuno. - The mysterious bridge crumbles and nobody ever passes there.

In Italian, when negative words like mai (never) and nessuno (nobody) come after the verb, you must still put non before the verb. You can chain multiple negative words together after the verb without them canceling each other out. The meaning translates smoothly to 'nobody ever passes' rather than a literal triple negative.

Could I change the word order to put nessuno before the verb?

Yes. If you put the negative subject nessuno before the verb, you must drop the non. You could write e nessuno ci passa mai, which is perfectly correct and means the exact same thing. Leaving nessuno at the very end just adds a bit of dramatic emphasis to 'nobody'.

Why is the verb sgretolarsi used with si here?

The verb sgretolarsi (to crumble or fall apart) is used reflexively because the bridge is undergoing the action itself. If you used sgretola without the si, it would mean the bridge is actively crumbling something else, which would require a direct object.

What is the function of ci in non ci passa?

In this sentence, ci is a locative pronoun meaning 'there' or 'across it', referring back to the bridge. Without ci, the sentence would vaguely mean 'nobody ever passes'. With ci, it specifically ties the action to passing over that particular bridge.