-th bbb bbh bbo bbs bbt bhb bhh bho bhs bht bob boh boo bos bot bsb bsh bso bss bst btb bth bto bts btt hbb hbh hbo hbs hbt hhb hhh hho hhs hht hob hoh hoo hos hot hsb hsh hss hst htb hth hto hts htt ob- obb obh obo obs obt ohh oho ohs oht oo- oob ooh ooo oos oot os- osb osh oso oss ost ot- otb oth oto ots ott sbb sbh sbo sbs sbt sh- shb shh sho shs sht sob soh soo sos sot ss- ssb ssh sso sss sst stb sth sto sts stt tbb tbh tbo tbs tbt th- thb thh tho ths tht to- tob toh too tos tot tsb tsh tso tss tst ttb tth tto tts ttt