-ous ffff ffss fftf fofo foof foos foot foso foss fost foto fots fott fous fout fsfo fssf ftos fuff fufu fuso fuss fust fusu futo futs futu off- offo offs offu ofst ofus ooff oofs oooo ooos oost oots oous osoo osos osso ossu osts oto- otof otoo otos otso otsu otto otts ottu otus ouff oust out- outo outs ouu- s-os sfos sfss sfsu sfts sofo soft soof soos soot soso soss sost soto sots sotu souf sous sout ssot sssf ssss ssts stfu stof stoo stos stot stou stsf stss stuf stus stut suf- suff sufs sufu suos sus- suso suss sust susu suto sutu suus tfot tfss toff tofo toft tofu toof toos toot toso toss tost tosu toto tots tott tous tout tsos tsou tssf tsst tsts ttff ttss tttt tuff tufo tuft tufu tuos tuss tust tuto tuts tutt tutu tuuo ufos uofo usfs usos ussf usss usst ussu usto usts usus utfo utto uttu uutf uuuu