srfi sris sros srpc srps srsp sscc ssce ssci sscp sscs ssec ssee ssep sses ssfc ssfl ssfp ssgs ssis sslc ssle sslp ssoc ssop sspc sspe sspf sspl sspo ssps ssrc ssrg ssri ssrl ssrs sssc sssf sssi ssss suc- succ suci sucr sucs suee suel suer sues sueu suf- sufc suff sufi sufr sufs sufu sug- suge sugg sugi sugo suie suig suio suir suis sul- sulc sule sulf suli sull sulo sulp sulu suor suos sup- supe supo supp supr sups sur- surc sure surf surg suri suro surp surr surs suru sus- suse susi suso susp suss susu suus u-ie u-rp ucci uccp ucel uces ucil ucio ucos ucrc ucsc ucsf ucsu ueir uele ueli uell uepi uers uess ufcu ufel ufer uffe ufip ufos ugcc ugcg ugeo ugep uggo uggs ugis ugli ugol ugos ugri ugro ugur uguu uies uige uile uipi uirr uise ulcc ulco ulee uleo ules ulfe ulic ulie ulle ulli ullo ullr ulo- uloc ulog ulos ulul ulus uocc uofg uofl uofo uolc uor- uore upci upcs upgo upic upie upis uplo upor upos uppc uppe uppp uppu upri upsc upse upsi upup urci ure- ures urfe urff urfi urge urgi urgu uric urie urif uris uriu urle urls uro- urol uroo urpo urre urri urse ursi urso urss ursu urup urur urus uscc usce uscf uscg usco uscs usee usef usel user uses usfc usfi usfl usfs usgo usgp usie usif usip usis usle uslp uslu usoc usoe usog usoi usos uspc uspo uspp usps ussc usse ussf ussr usss ussu usui usul usus uucp uulu uuoc uuri uusi uuuu