bbbb bbbs bblb bbls bffl bffs bfsi bfts bftt bibb bibi bibl bibs biff bifi biis bili bill bils bilt bilu bis- bisl biss bist bisu bits bitt bitu blbt blis blit blls blss blst blts blub bluf blus blut bsff bsfs bsts btss bttb btus bubb bubi bubs bubu buff buif buis buit buiu bulb buli bull buls bult bulu busi buss bust busu but- buti buts butt buus fbis fbus ffff ffii ffss fftf fibs fiff fifi fift fiii fiil fili fill fils fisi fiss fist fisu fiti fits fitt flii flis flit flts flub fluf flus fsfi fssf ft-l ftii ftlb ftub fubb fubs fubu fuff fufu fuil fuit fuli full fuls fulu fusi fuss fust fusu futi futs futu ibfi ibis ibsf ibss ibtb ibtl ibts ibus ifbb ifil ifis ifit ifsb iiii iiis iiit iisi iist iisu iitt ilis ilit ill- illi ills illt ilts ilus ilut isbl isbt isil isis isit isls issf issi isss issu isti ists isus itbs itif itil itis itll itsf itsi itsu ittf iuiu iuss iust lfts libs libu liff lifl lift liii liis lilb lili lill lils lilt lilu lisi liss list lisu litb liti litl lits litt litu liuf lius liut llbs llll lsbu lsts ltbf ltbl ltib ltsi lubs luff luft lufu luif luis luit luli lull lulu lusi luss lust luti luts s-ib s-ii sbbs sbsi sbst sbus sfls sfss sfsu sfts sibi sibs sibu siff sifl sift sifu siit sil- silf sili sill sils silt silu sisi siss sist sisu sit- siti sits sitt situ siui sius siut sl-i slft slib slit slst slsu slts slub slut ssfl ssis ssit sslt sssb sssf sssi ssss sstb sstl ssts stbs stfu stib stif stil stis stit stlt stsf stsi stss stub stuf stul stus stut sub- subb subi subl subs suf- suff sufi sufs sufu suis suit sul- sulf suli sull sult sulu sus- susi suss sust susu suti sutu suus tbbs tbil tbit tbst tfsi tfss tibi tibs tibu tiff tift tiit tiiu till tils tilt tisb tisi tiss tist titi tits titt titu tlli tsfl tsis tssf tssi tsst tsts tsui ttbb ttff ttss tttt ttul tubb tubs tubu tuff tufi tuft tufu tuil tuis tuit tuiu tuli tull tulu tusi tuss tust tuti tutl tuts tutt tutu ubbi ubii ubis ubit ubli ubls ubtf uist uits ulft ulli ulti ults ultt ulul ulus usbl usbs usfi usfl usfs usif usis uslu ussb ussf usss usst ussu ustb usti usts usui usul usus util utis utsl utti uttu uulu uusi uutf uuuu