-ol bbb bbl bbm bbo bbs bbt blb bll blm blo bls blt bmb bml bmm bmo bms bmt bob bol bom boo bos bot bsb bsl bsm bso bss bst btb btl btm bto bts btt lbb lbl lbm lbo lbs lbt llb lll llm llo lls llt lmb lml lmm lmo lms lmt lob lol lom loo los lot lsb lsl lsm lso lss lst ltb ltl ltm lto lts ltt m-o mbb mbl mbm mbo mbs mbt mlb mll mlm mlo mls mlt mmb mml mmm mmo mms mmt mob mol mom moo mos mot msb msl msm mso mss mst mtb mtl mtm mto mts mtt ob- obb obl obm obo obs obt olb oll olm olo ols olt om- omb oml omm omo oms omt oo- oob ool oom ooo oos oot os- osb osl osm oso oss ost ot- otb otl otm oto ots ott sbb sbl sbm sbo sbs sbt slb sll slm slo sls slt smb sml smm smo sms smt sob sol som soo sos sot ss- ssb ssl ssm sso sss sst stb stl stm sto sts stt tbb tbl tbm tbo tbs tbt tll tlm tlo tls tlt tmb tml tmm tmo tms tmt to- tob tol tom too tos tot tsb tsl tsm tso tss tst ttb ttl ttm tto tts ttt