ffff ffii ffrr ffss fftf ffun fiff fifi fift fiii fini finn fins fint firn firs fisi fiss fist fisu fiti fits fitt fnrs fnuf frin fris frit frns frst frun fsfi fssf ftii ftrs ftsr fuff fufu fuir fuit funf funs funt fur- furi furn furr furs furt fusi fuss fust fusu futi futs futu ifis ifit ifni ifnr ifns ifrf ifri iftn iiii iiis iiit iirs iisi iisr iist iisu iitr iitt infi infs inis init inni innr inns innu inri inrs inss inst insu inti intn intr ints intu inui inun inus irfu iri- irin iris irri irrs irsf irtf irti irts irun irus isin isis isit isnt isri issf issi issr isss issu isti istr ists isus itif itin itis itrf itri itrs itsf itsi itsu ittf itur iuiu iuss iust n-ii nfff nfrs nfsr nfsu niff nift niir niit niiu nini nins nirs nirt niru nisi niss nist nisu nitf niti nitr nits niur nnit nnnn nnss nntn nrts nsfs nsin nsis nsnr nssf nssr nsss nsts nstu ntfs ntis ntnu ntru ntsf ntss ntsu nttr ntui nuff nuin nuit nunn nuns nunt nuri nurn nurr nurs nurt nuru nusi nuss nust nusu nuts nutt nutu riff rifs rift rifu riif riin riis rinf rinn riri rirs risi riss rist risu riti rits ritt ritu rius rnin rnnt rnut rrif rrrr rrun rsis rsnn rsnr rsts rstu rtns rtss rtts ruff ruft ruif ruin ruis ruit runf runi runn runs runt ruri rurs ruru rusi russ rust rusu ruti ruts rutt rutu ruun s-ii sfnt sfss sfsu sfts siff sifr sift sifu siit sini sinn sins sint sinu sirf siri sirr sirs sirt siru sisi siss sist sisu sit- siti sitn sits sitt situ siui sius siut snfu snir snit snns snrs sntr snur snus srfi sris srni srnn srtr ssin ssis ssit ssns ssri ssrs sssf sssi ssss ssts stfn stfu stif stir stis stit stnn stnr stns stri strn strs stru stsf stsi stss sttr stuf stun stur stus stut suf- suff sufi sufr sufs sufu suin suir suis suit sun- suni sunn suns sunt sunu sur- surf suri surn surr surs surt suru sus- susi suss sust susu suti sutu suus tfin tfrs tfsi tfss tiff tift tiit tiiu tini tinn tins tint tinu tiri tirr tirs tiru tisi tiss tist titi tits titt titu tnts tnut trfr tri- trif trin tris trit trsi trst trtr trun trus trut truu tsin tsis tssf tssi tssr tsst tsts tsui tsun ttff ttfn ttss tttt tuff tufi tuft tufu tuin tuis tuit tuiu tuni tunn tuns tunu turf turi turn turr turs turt turu tusi tuss tust tuti tuts tutt tutu uint uirr uist uits uni- unif unii unin unir unis unit unni unns unrf unrs uns- unst unts unus unut urff urfi urft urif urin uris uriu urni urns urri ursi urss ursu urts urun urur urus urut usfi usfs usif usin usis usnr usnu ussf ussr usss usst ussu usti usts usui usun usus utin utis utri utti uttu uuni uuri uusi uutf uuuu