b-room bbbbbb bo-hoo bogoro bombom bombur booboo boogum boohoo boom-o borbor borogo boromo bororo borugh boubou bougou bourgh bourou brohug bromo- broogh brough brubru bububu bugbug bumboo burbur burgoo burgor burgum burhou gobbur goboom gogoro googoo gooroo gorgor gourou grough grugru gubgub gurbru gurgum gurugu h-bomb h-hour ho-hum hogoro hohoho hoohoo hooroo horgr hororo horror hubbub hububb huh-uh humbug humhub humhum hummum humour huoguo hurroo hurumu mbombo mbomou mm-hmm mogoro mohoro mohuhu mommur moogoo moomoo mormor mormur morogo mourou muggur mugumu muguru muhugu muhuhu muhurr muhuru murmur muumuu obourg ohohoh ombro- oohooh oooooo oromoo orrho- orrour rhogog rhomb- robo-g robomb romour roogoo rubro- rubrum ruhroh rumbur rumohr rumour ubombo uh-huh um-hum urhobo urughu