-ol bbb bbe bbk bbl bbo bbt be- beb bee bek bel beo bet bkb bke bkk bkl bko bkt blb ble blk bll blo blt bob boe bok bol boo bot btb bte btk btl bto btt ebb ebe ebk ebl ebo ebt eeb eee eek eel eeo eet ekb eke ekl eko ekt elb ele elk ell elo elt eo- eob eoe eok eol eoo eot etb ete etk etl eto ett k-t kbb kbe kbk kbl kbo ke- keb kee kek kel keo ket kkb kke kkk kkl kkt kl- klb klo klt kob koe kok kol koo kot ktb kte ktk ktl kto ktt lbb lbe lbk lbl lbo lbt leb lee lek lel leo let lkb lkl lkt llb lle llk lll llo llt lob loe lok lol loo lot ltb lte ltk ltl lto ltt ob- obb obe obk obl obo obt oeb oee oel oeo oet okb oke okk okl oko olb ole olk oll olo olt oo- oob ook ool ooo oot ot- otb ote otk otl oto ott tbb tbe tbk tbl tbo tbt te- teb tee tek tel teo tet tkb tke tkk tkl tko tkt tle tlk tll tlo tlt to- tob toe tok tol too tot ttb tte ttk ttl tto ttt