aaaa aaaf aaas aafa aaff aaoo aasa aasf aass afaa afao affa affo affs afoa afoo afsa aoss asaa asaf asao asas asfa asof asos assa asso asss faaa faas fafa faff fafo fasa faso fass ffff ffsa ffss foaf fofo foof foos fosa foso foss fsas fsfo fssa fssf oafo oafs oass ofas off- offa offo offs ooaa ooff oofs oooo ooos oosa osaf osas osfa osoo osos ossa osso s-os saaf saas safa saff safo saos sasa sasf saso sass sfas sfos sfss soas sofa sofo soof soos sosa soso soss ssaa ssao ssas sssa sssf ssss