He had already struggled through one Friday’s worth, with Hermione sitting next to him intoning "ignore them, ignore them, ignore them" under her breath, and he couldn’t see why today should be any better.
There are no more uses of "intone" in the book.
Show samples from other sources
As her head went beneath the surface she heard Jem intoning, "Jean Louise Finch, I baptize you in the name of—"
Harper Lee -- Go Set a Watchman
"Forgive him, oh hallowed Aspirant," Tristas intones, blue eyes sparkling.