a-a a-b a-i aaa aab aai aar aau ab- aba abb abi abr abu ai- aia aib aii air aiu ar- ara arb ari arr aru au- aua aub aui aur b-u baa bab bai bar bau bba bbb bbi bbr bbu bi- bia bib bii bir biu bra brb bri brr bru bua bub bui bur buu ia- iaa iab iai iar iau iba ibb ibi ibr ibu iia iib iii iir iiu ir- ira irb iri irr iru iu- iua iub iui iur ra- raa rab rai rar rau rba rbb rbi rbr rbu ria rib rii rir rra rrb rri rrr rru rua rub rui rur ruu ua- uaa uab uai uar uau uba ubb ubi ubr ubu uia uib uii uir uiu ur- ura urb uri urr uru uua uur uuu