-er -ol b-u bbb bbe bbl bbo bbr bbt bbu bbx be- beb bee bel beo ber bet beu bex blb ble bll blo blr blt blu blx bob boe bol boo bor bot bou box brb bre brl bro brr brt bru brx btb bte btl bto btr btt btu btx bub bue bul buo bur but buu bux bxb bxl bxo bxx ebb ebe ebl ebo ebr ebt ebu ebx eeb eee eel eeo eer eet eex elb ele ell elo elr elt elu elx eo- eob eoe eol eoo eor eot eou erb ere erl ero err ert eru etb ete etl eto etr ett etu etx eu- eub eue eul eur eut eux ex- exe exl exo exr ext exu exx lbb lbe lbl lbo lbr lbt lbu lbx leb lee lel leo ler let leu lex llb lle lll llo llr llt llu lob loe lol loo lor lot lou lox lrb lro lrr lrt lru ltb lte ltl lto ltr ltt ltu ltx lub lue lul luo lur lut luu lux lxo lxr lxx ob- obb obe obl obo obr obt obu obx oeb oee oel oeo oer oet oex olb ole oll olo olt olu oo- oob ool ooo oor oot oox or- orb ore orl oro orr ort oru orx ot- otb ote otl oto otr ott otu ou- oue oul ouo our out ox- oxb oxo oxt oxx rbb rbe rbl rbo rbr rbt rbu rbx re- reb ree rel reo rer ret reu rex rle rll rlo rlr rlt rlu rob roe rol roo ror rot rou rox rrb rrl rrr rrt rru rtb rte rtl rto rtr rtt rtu rtx rub rue ruo rur rut ruu rux rxr t-x tbb tbe tbl tbo tbr tbt tbu te- teb tee tel teo ter tet teu tex tle tll tlo tlr tlt tlu tlx to- tob toe tol too tor tot tou tox trb tre trl tro trr trt tru trx ttb tte ttl tto ttr ttt ttu ttx tub tue tul tuo tur tut tuu tux txe txl txt txu ubb ube ubl ubo ubr ubt ubu ubx ueb uee uel uer uet ulb ule ull ulo ulr ult ulu uob uoe uol uoo uor uot uox ur- urb ure url uro urr urt uru urx utb ute utl uto utr utt utu utx uue uur uut uuu uxb uxo uxr uxt uxu xbe xbl xbr xbx xee xel xer xet xeu xex xlb xlr xlt xoo xor xot xox xrt xrx xtr xtx xue xul xxl xxo xxx