a-a aaa aak aao aap aas aka akk ako akp aks aoa aok aoo aop aos ap- apa apk apo app aps as- asa ask aso asp ass ka- kaa kak kao kap kas kkk kkp kks koa kok koo kop kos kpa kpk kpo kpp kps ksa ksk kso ksp kss oaa oak oao oap oas oka okk oko okp oks oo- ooa ook ooo oop oos op- opa opk opo opp ops os- osa osk oso osp oss p-p paa pak pao pap pas pka pko pkp pks poa pok poo pop pos ppa ppk ppo ppp pps ps- psa psk pso psp pss saa sak sao sap sas sk- ska skk sko skp sks soa sok soo sop sos spa spk spo spp sps ss- ssa ssk sso ssp sss