bbbb bbeb bblb bbox bebb bebe bebo beeb beef beel befe beff befo bele bell belo beo- beof bffl bleb blee bleo blob bloo bobb bobe bobo boee boef boel boeo bofe boff bole boll bolo boob booe boof bool boox ebbo ebel eboe ebol eboo ebox eeee eefe eefl eele efeo el-b elbe elbo elee elef eleo elex elfe elle ello eole eolo exel exfo exo- fble febo feeb feel fefe feff fefo fele felf fell felo feof ffee ffff flee flex flob floe floo flox fofo fole foll folo folx foof fool foxe foxx lebo leef leel lefe leff lele lell lelo leof leox lexx llef llll lloo lob- lobb lobe lobo loeb lofe loff lole loll lolo loob looe loof lool lox- loxo lxxx o-eo obbo obel obex oble oboe obol obox oele off- offe offo olbo ole- olef oleo olfe olle ollo olof oobe ooff oolo oooo oxo- oxof oxox oxxo xbee xbel xbox xefe xexe xlox xolo xoxo xxxo xxxx