-er b-u bbb bbe bbg bbh bbk bbo bbr bbu bbx be- beb bee beg beh bek beo ber beu bex bgb bge bgg bgh bgk bgo bgr bgu bgx bhb bhe bhg bhh bhk bho bhr bhu bhx bkb bke bkg bkk bko bkr bkx bob boe bog boh bok boo bor bou box brb bre brg brh brk bro brr bru brx bub bue bug buh buk buo bur buu bux bxb bxo bxx ebb ebe ebg ebh ebk ebo ebr ebu ebx eeb eee eeg eek eeo eer eex egb ege egg egh ego egr egu egx ehb ehe ehg ehh eho ehr ehu ekb eke ekg ekh eko ekr eku eo- eob eoe eog eoh eok eoo eor eou erb ere erg erh erk ero err eru eu- eub eue eug eur eux ex- exe exh exo exr exu exx gbe gbg gbh gbk gbo gbr gbu gbx ge- geb gee geg geh gek geo ger geu gex ggb ggg ggh ggo ggr ggu ghb ghe ghg ghh gho ghr gkb gkh gko gob goe gog goh gok goo gor gou gox grb gre grg grh grk gro grr gru grx gu- gub gue gug guk guo gur guu hbb hbe hbg hbh hbk hbo hbr hbu hbx he- heb hee heg heh hek heo her heu hex hgb hge hgg hgh hgk hgo hgr hgu hhb hhe hhg hhh hhk hho hhr hhu hkb hkg hkh hkk hko hkr hku hob hoe hog hoh hok hoo hor hou hox hr- hrb hre hrg hrh hrk hro hrr hru hub hue hug huh huk huo hur huu hux kbb kbe kbh kbk kbo kbr kbu kbx ke- keb kee keg keh kek keo ker kex kgb kgh kgo kgu kgx khe khh khk kho khr khu kkb kke kkh kkk kkr kku kob koe kog koh kok koo kor kou krg krk kro krr kru kub kue kug kuh kuk kur kuu kxo ob- obb obe obg obh obk obo obr obu obx oeb oee oeg oeh oeo oer oex oge ogg ogh ogo ogx ohe ohg ohh oho ohr ohu okb oke okg okk oko okr oku oo- oob oog ooh ook ooo oor oox or- orb ore org orh ork oro orr oru orx ou- oue ouh ouk ouo our ox- oxb oxo oxx rbb rbe rbg rbh rbk rbo rbr rbu rbx re- reb ree reg reh rek reo rer reu rex rgb rge rgg rgh rgk rgo rgr rgx rh- rhb rhe rhg rhh rho rhr rhu rkb rke rkg rkk rko rku rob roe rog roh rok roo ror rou rox rrb rrg rrh rrk rrr rru rub rue rug ruh ruk ruo rur ruu rux rxr ubb ube ubg ubh ubk ubo ubr ubu ubx ueb uee ueg ueh uer ugb uge ugg ugh ugk ugo ugr ugu ugx uhb uhe uhh uho uhr uhu ukb uke ukk ukr uku uob uoe uog uok uoo uor uox ur- urb ure urg urk uro urr uru urx uue uug uur uuu uxb uxo uxr uxu xbe xbr xbx xee xeg xer xeu xex xge xkb xke xog xok xoo xor xox xrx xue xxo xxx