bbbb bbbs bblb bbls blls blob bloo blss bobb bobo bobs boll bolo bols boob bool boor boos bor- boro borr bors boso boss brls brob brol broo bror bros brrr brrs brsb brsr bsos lblr lbos lbrs llbs llll lloo lob- lobb lobo lobs loll lolo lols loob lool loor loos loro lors loso loss lrrr ls-r lsso lssr obbo obls obol obor obos obro obsr obss olbo ollo olor olos oolo oooo ooos orbb orbo orbs orlo oro- oror oros orro orrs orso oslo osoo osor osos osro ossb osso rbbb rbbr rbbs rbsl rbss rlls rob- robb robo robs roll rolo roob rool roor roos roro roso ross rrrr rsos rssl s-os sbbs sbor slob sloo slos slrs sobo sobr sobs soll solo solr sols sool soor soos sorb soro sorr sors soso soss sros ssbr ssrl ssrs sssb ssss