| drones(noun, verb, vibrations, rumbles, grumbles) |
| hums(noun, verb, rumbles) |
| whirs(noun, verb, sibilates, sibilations) |
| whispers(noun, verb, sibilates, sibilations) |
| hisses(noun, verb, sibilates, sibilations) |
| thrums(noun, verb, rumbles) |
| zips(noun, verb, sibilates, sibilations) |
| chants(noun, verb, waits, rumbles, shouts) |
| lisps(noun, verb, sibilates, sibilations) |
| murmurs(noun, verb, traces, vibrations, hints) |
| rolls(noun, verb, rumbles) |
| rumbles(noun, verb, rumbles) |
| sizzles(noun, verb, sibilates, sibilations) |
| sniffles(noun, verb, sibilates, sibilations) |
| snores(noun, verb, sibilates, sibilations) |
| snorts(noun, verb, sibilates, sibilations) |
| snuffles(noun, verb, sibilates, sibilations) |
| sputters(noun, verb, sibilates, sibilations) |
| wheezes(noun, verb, sibilates, sibilations) |
| whistles(noun, verb, sibilates, sibilations) |