-er -up a-a a-b aaa aab aae aap aar aau ab- aba abb abe abp abr abu aea aeb aee aep aer aeu ap- apa apb ape app apr apu ar- ara arb are arp arr aru au- aua aub aue aup aur b-p b-u baa bab bae bap bar bau bba bbb bbe bbp bbr bbu be- bea beb bee bep ber beu bpa bpb bpe bpp bpr bpu bra brb bre brp brr bru bua bub bue bup bur buu eaa eab eae eap ear eau eba ebb ebe ebp ebr ebu eea eeb eee eep eer ep- epa epb epe epp epr epu era erb ere erp err eru eu- eua eub eue eup eur p-p paa pab pae pap par pau pba pbb pbe pbp pbr pbu pea peb pee pep per peu ppa ppb ppe ppp ppr ppu pra prb pre prp prr pru pua pub pue pup pur puu ra- raa rab rae rap rar rau rba rbb rbe rbp rbr rbu re- rea reb ree rep rer reu rpa rpb rpe rpp rpr rpu rra rrb rrp rrr rru rua rub rue rup rur ruu ua- uaa uab uae uap uar uau uba ubb ube ubp ubr ubu uea ueb uee uep uer up- upa upb upe upp upr upu ur- ura urb ure urp urr uru uua uue uur uuu