bbbb bbdd bbeb bbet bd-r bebb bebe bede beeb beed beer beet berd bere berr bert bete bett betv brdt breb bred bree brer bret brev brrr btdt btrt bttb d-tv dbtt dddd ddre ddtv debe debt dedd dede deeb deed deer deet deev der- derb dere derr derv dete detr deve dred dree dret drev dted dvdr ebbr ebed eber edde ede- eder edtv edve eede eeee eete erbb erbe erde ereb ered erer eret erev erre erve etbr etee eter etre ette evdb ever evet evre rbbb rbbr rder rdev rebb rebe redd rede redr reeb reed reet reev rerd rere rert retd rete retr rett revd reve rred rrrr rtdt rtee rtve rved rver tbrb tddb tdtv tedd tede teed teer teet teev ter- tere terr tete tetr tett tre- tred tree tret trev trte trtr ttbb tter tttt tver tvrr tvtv vder vdre vede veer veet ver- verb verd vere vert vete vetr veve vred vret vver vvvv