For the duration, no sound can be created within or pass through a 20-foot-radius sphere centered on a point you choose within range. Any creature or object entirely inside the sphere is immune to thunder damage, and creatures are deafened while entirely inside it. Casting a spell that includes a verbal component is impossible there.

(enter in keywords and delimit them by space, IE, "fire acid". Not all spells need keywords, limit keywords to effects/realm of spell)