cccc cccs ccoc ccss ccst cctc cctt coco coct coos coot cosc coso coss cost cosy cotc coto cots cott coty coyo coys coyt cscc csco cscs csos csot cstc csto csts csys ctos ctot ctsc ctss ctts cyc- cycc cycs cyst cyt- cyto cyy- cyyc occc occt ocos oct- octo octs octy ocys oooo ooos oost oots ooty oscc osco osoo osos osso ossy ostc osts osyt oto- otoo otos otoy otso otto otts oyss oyst s-os sccc sccs scct sccy scoo scot scsc scso scst sctc scto scts soco socs socy soos soot sooy soso soss sost sotc soto sots soyo soys soyt sscc sscs ssoc ssot sssc ssss sstc ssts stcc stcs stoo stos stot stoy stss sttc stys syco syso syss syst sytt tccc tcos tctc tcts to-y toco toos toot tosc toso toss tost tosy totc toto tots tott toty toyo toys toyt tscc tsos tsoy tsst tstc tsts tsys ttoy ttss tttt ttys tyco tyss tyst tyto tytt tyty yccc yctc yoot yoso yost yott yoyo ysco yyyy