-er bbb bbe bbh bbo bbr be- beb bee beh beo ber bhb bhe bhh bho bhr bob boe boh boo bor brb bre brh bro brr ebb ebe ebh ebo ebr eeb eee eeo eer ehb ehe ehh eho ehr eo- eob eoe eoh eoo eor erb ere erh ero err hbb hbe hbh hbo hbr he- heb hee heh heo her hhb hhe hhh hho hhr hob hoe hoh hoo hor hr- hrb hre hrh hro hrr ob- obb obe obh obo obr oeb oee oeh oeo oer ohe ohh oho ohr oo- oob ooh ooo oor or- orb ore orh oro orr rbb rbe rbh rbo rbr re- reb ree reh reo rer rh- rhb rhe rhh rho rhr rob roe roh roo ror rrb rrh rrr