-er b-u bbb bbe bbk bbn bbo bbr bbs bbt bbu be- beb bee bek ben beo ber bes bet beu bkb bke bkk bkn bko bkr bks bkt bnb bne bnk bnn bno bnr bns bnt bnu bob boe bok bon boo bor bos bot bou brb bre brk brn bro brr brs brt bru bsb bse bsk bsn bso bsr bss bst bsu btb bte btk btn bto btr bts btt btu bub bue buk bun buo bur bus but buu ebb ebe ebk ebn ebo ebr ebs ebt ebu eeb eee eek een eeo eer ees eet ekb eke eko ekr eks ekt eku en- enb ene enk enn eno enr ens ent enu eo- eob eoe eok eon eoo eor eos eot eou erb ere erk ern ero err ers ert eru es- esb ese esk esn eso esr ess est esu etb ete etk etn eto etr ets ett etu eu- eub eue eun eur eus eut k-t kbb kbe kbk kbn kbo kbr kbs kbu ke- keb kee kek ken keo ker kes ket kkb kke kkk kkn kkr kks kkt kku kn- kne knk knn kno knr knt knu kob koe kok kon koo kor kos kot kou krk krn kro krr krs krt kru ksb kse ksk ksn kso ksr kss kst ksu ktb kte ktk ktn kto ktr kts ktt ktu kub kue kuk kun kur kus kut kuu nbb nbe nbk nbn nbo nbr nbs nbt nbu ne- neb nee nek nen neo ner nes net neu nke nkk nkn nko nkr nks nkt nku nnb nne nnk nnn nno nns nnt nnu no- nob noe nok non noo nor nos not nou nrb nre nrk nrn nro nrr nrs nrt nru nsb nse nsk nsn nso nsr nss nst nsu ntb nte ntk ntn nto ntr nts ntt ntu nub nue nuk nun nuo nur nus nut nuu ob- obb obe obk obn obo obr obs obt obu oeb oee oen oeo oer oes oet okb oke okk oko okr oks oku on- onb one onk onn ono onr ons ont onu oo- oob ook oon ooo oor oos oot or- orb ore ork orn oro orr ors ort oru os- osb ose osk osn oso osr oss ost osu ot- otb ote otk otn oto otr ots ott otu ou- oue ouk oun ouo our ous out rbb rbe rbk rbn rbo rbr rbs rbt rbu re- reb ree rek ren reo rer res ret reu rkb rke rkk rko rks rkt rku rnb rnn rno rnr rns rnt rnu rob roe rok ron roo ror ros rot rou rrb rrk rrn rrr rrs rrt rru rsb rse rsk rsn rso rsr rss rst rsu rtb rte rtk rtn rto rtr rts rtt rtu rub rue ruk run ruo rur rus rut ruu sbb sbe sbk sbn sbo sbr sbs sbt sbu se- seb see sek sen seo ser ses set seu sk- skb ske skk sko skr sks skt sku snb sne snk snn sno snr sns snt snu sob soe sok son soo sor sos sot sou sr- srb sre srk srn sro srr srs srt ss- ssb sse ssk ssn sso ssr sss sst ssu stb ste stk stn sto str sts stt stu sub sue suk sun suo sur sus sut suu tbb tbe tbk tbn tbo tbr tbs tbt tbu te- teb tee tek ten teo ter tes tet teu tkb tke tkk tko tkr tks tkt tnb tne tnk tnn tno tnr tns tnt to- tob toe tok ton too tor tos tot tou trb tre trk trn tro trr trs trt tru tsb tse tsk tsn tso tsr tss tst tsu ttb tte ttk ttn tto ttr tts ttt ttu tub tue tuk tun tuo tur tus tut tuu ubb ube ubk ubn ubo ubr ubs ubt ubu ueb uee uen uer ues uet ukb uke ukk ukn ukr uku un- unb une unk unn uno unr uns unt unu uob uoe uok uon uoo uor uos uot ur- urb ure urk urn uro urr urs urt uru usb use usk usn uso usr uss ust usu utb ute utk utn uto utr uts utt utu uue uun uur uus uut uuu