b-p bbb bbo bbp bbr bbs bbt bbx bob boo bop bor bos bot box bpb bpo bpp bpr bps bpt bpx brb bro brp brr brs brt brx bsb bso bsp bsr bss bst bsx btb bto btp btr bts btt btx bxb bxo bxx ob- obb obo obp obr obs obt obx oo- oob ooo oop oor oos oot oox op- opb opo opp opr ops opt opx or- orb oro orp orr ors ort orx os- osb oso osp osr oss ost osx ot- otb oto otp otr ots ott ox- oxb oxo oxt oxx p-p pbb pbo pbp pbr pbs pbt pbx pob poo pop por pos pot pox ppb ppo ppp ppr pps ppt ppx prb pro prp prr prs prt prx ps- psb pso psp psr pss pst psx pt- ptb pto ptp ptr pts ptt ptx pxr pxs pxt rbb rbo rbp rbr rbs rbt rbx rob roo rop ror ros rot rox rpb rpo rpp rpr rps rpt rpx rrb rrp rrr rrs rrt rsb rso rsp rsr rss rst rsx rtb rto rtp rtr rts rtt rtx rxp rxr rxs sbb sbo sbp sbr sbs sbt sbx sob soo sop sor sos sot sox spb spo spp spr sps spt spx sr- srb sro srp srr srs srt srx ss- ssb sso ssp ssr sss sst ssx stb sto stp str sts stt stx sxs sxt t-x tbb tbo tbp tbr tbs tbt to- tob too top tor tos tot tox tpb tpo tpp tpr tps tpt tpx trb tro trp trr trs trt trx tsb tso tsp tsr tss tst tsx ttb tto ttp ttr tts ttt ttx txs txt xbr xbx xoo xop xor xos xot xox xpb xpo xpp xps xpt xrt xrx xsb xsp xss xst xtp xtr xts xtx xxo xxp xxx