k-os kkkk kkoo kkor kkpk kkps kkrk kkro kkrr kkrs kksp kksr kkss kokk koko kokp kokr koks kook kooo koop koor koos kopp kopr kops kork koro korr kors kos- koso kosp kosr koss kpkk kpkr kpok kpoo kpop kppk kppo kppp kppr kprk kpro kprp kprr kprs kpso kpsp krkk krko krkr krks krok kroo krop kror kros krpr krps krrk krro krrr krrs krsk krsr krss kskk ksko kskr ksks ksok ksoo ksop ksor ksos kspk kspo kspr ksps ksro ksrp ksrr ksrs ksso kssr ksss okko okok okor okpo okro okso oooo ooos oops opo- opor opos oppo opps orko oro- orok oror oros orps orro orrs orsk orso osoo osor osos osro osso poko pook poop poor poos pop- popo popp pops pork poro porr pors posk poso poss ppos pppo pppp ppps ppss pro- proo prop pros prps prrs prso prss psos pspp pspr psps psrk psrp psso rkos rkss rokk roko rokr roks rook roop roor roos ropo rops rork roro roso rosp ross rpos rpps rrrr rrsp rsos rspk rspo rsps s-os skop skor skpo skss sokk soko sook soop soor soos sopo sopp sops soro sorr sors soso soss spkr spok spoo spop spor spos spps spro sprs spso spsp spss sros srps srsp ssop sspo ssps ssrs ssss