a-a a-b aaa aab aar aau aay ab- aba abb abr abu aby ar- ara arb arr aru ary au- aua aub aur ay- aya ayr ayu b-u baa bab bar bau bay bba bbb bbr bbu bby bra brb brr bru bry bua bub bur buu buy by- bya byr byu ra- raa rab rar rau ray rba rbb rbr rbu rra rrb rrr rru rua rub rur ruu ruy ry- rya ryr ryu ryy ua- uaa uab uar uau uay uba ubb ubr ubu uby ur- ura urb urr uru ury uua uur uuu uyu yaa yab yar yau yay ybr yby yra yru yua yur yuu yuy yyb yyu yyy