-er a-a a-c a-t aaa aac aae aak aao aap aar aat ac- aca acc ace ack aco acp acr act aea aec aee aek aeo aep aer aet aka akc ake akk ako akp akr aoa aoc aoe aok aoo aop aor aot ap- apa apc ape apk apo app apr apt ar- ara arc are ark aro arp arr art at- ata atc ate ato atp atr att c-- caa cac cae cak cao cap car cat cca ccc cce cck cco ccp ccr cct ce- cea cec cee cek ceo cep cer cet cka ckc cko ckt co- coa coc coe cok coo cop cor cot cpa cpc cpe cpk cpo cpp cpr cpt cra crc cre crk cro crp crr crt cta ctc cte ctk cto ctp ctr ctt eaa eac eae eak eao eap ear eat ec- eca ecc ece eck eco ecr ect eea eec eee eek eeo eep eer eet eka ekc eke eko ekp ekr ekt eo- eoa eoc eoe eok eoo eop eor eot ep- epa epc epe epo epp epr ept era erc ere erk ero erp err ert eta etc ete etk eto etp etr ett k-t ka- kaa kac kae kak kao kap kar kat kca kcc kce kck kcp kcr kct ke- kea kec kee kek keo kep ker ket kkc kke kkk kkp kkr kkt koa koc koe kok koo kop kor kot kpa kpc kpe kpk kpo kpp kpr kpt kra krc krk kro krp krr krt kta ktc kte ktk kto ktp ktr ktt oaa oac oae oak oao oap oar oat oc- oca occ ock oco ocp ocr oct oea oec oee oeo oep oer oet oka okc oke okk oko okp okr oo- ooa ooc ook ooo oop oor oot op- opa opc ope opk opo opp opr opt or- ora orc ore ork oro orp orr ort ot- ota otc ote otk oto otp otr ott p-p paa pac pae pak pao pap par pat pca pcc pce pck pco pcp pcr pct pea pec pee pek peo pep per pet pka pkc pke pko pkp pkr pkt poa poc poe pok poo pop por pot ppa ppc ppe ppk ppo ppp ppr ppt pra prc pre prk pro prp prr prt pt- pta ptc pte ptk pto ptp ptr ptt ra- raa rac rae rak rao rap rar rat rca rcc rce rco rcp rcr rct re- rea rec ree rek reo rep rer ret rkc rke rkk rko rkp rkt roa roc roe rok roo rop ror rot rpa rpc rpe rpk rpo rpp rpr rpt rra rrc rrk rrp rrr rrt rta rtc rte rtk rto rtp rtr rtt taa tac tae tak tao tap tar tat tca tcc tce tck tco tcp tcr tct te- tea tec tee tek teo tep ter tet tka tkc tke tkk tko tkp tkr tkt to- toa toc toe tok too top tor tot tpa tpc tpe tpk tpo tpp tpr tpt tra trc tre trk tro trp trr trt tta ttc tte ttk tto ttp ttr ttt