-er -ey bbb bbe bbk bbn bbo bbr bby be- beb bee bek ben beo ber bey bkb bke bkk bkn bko bkr bnb bne bnk bnn bno bnr bob boe bok bon boo bor boy brb bre brk brn bro brr bry by- bye byk byn byo byr ebb ebe ebk ebn ebo ebr eby eeb eee eek een eeo eer eey ekb eke eko ekr eky en- enb ene enk enn eno enr eny eo- eob eoe eok eon eoo eor erb ere erk ern ero err ery eye eyn eyo eyr kbb kbe kbk kbn kbo kbr ke- keb kee kek ken keo ker key kkb kke kkk kkn kkr kky kn- kne knk knn kno knr kob koe kok kon koo kor koy krk krn kro krr kry kye kyn kyo kyr nbb nbe nbk nbn nbo nbr ne- neb nee nek nen neo ner ney nke nkk nkn nko nkr nky nnb nne nnk nnn nno no- nob noe nok non noo nor noy nrb nre nrk nrn nro nrr nry nye nyk nyn nyo nyy ob- obb obe obk obn obo obr oby oeb oee oen oeo oer oey okb oke okk oko okr on- onb one onk onn ono onr ony oo- oob ook oon ooo oor or- orb ore ork orn oro orr ory oye oyo rbb rbe rbk rbn rbo rbr re- reb ree rek ren reo rer rey rkb rke rkk rko rky rnb rnn rno rnr rny rob roe rok ron roo ror roy rrb rrk rrn rrr ry- rye ryk ryn ryo ryr ryy ybe ybr yby yeb yee yek yen yeo yer yey ykk ykn yne ynk ynn yny yob yoe yok yon yoo yor yoy yre yrn yro yyb yye yyy