oooo ooos oops oost ootp oots opo- opos oppo opps opto opts osoo osos osso osts oto- otoo otos otpp otso otto otts poop poos poot pop- popo popp pops popt poso poss post poto pots pott ppos pppo pppp ppps ppss ppts pptt psos pspp psps psso psst psts ptop s-os soop soos soot sopo sopp sops soso soss sost soto sotp sots spoo spop spos spot spps spso spsp spss spst spto spts ssop ssot sspo ssps sspt ssss sstp ssts stoo stop stos stot stpp stps stss toos toot top- topo topp tops topt toso toss tost toto tots tott tppp tptp tsop tsos tspo tsps tspt tsst tsts ttop ttss tttt