a-a a-b a-i aaa aab aai aan aao aar aau ab- aba abb abi abn abo abr abu ai- aia aib aii ain aio air aiu an- ana anb ani ann ano anr anu aoa aob aoi aon aoo aor aou ar- ara arb ari arn aro arr aru au- aua aub aui aun auo aur b-u baa bab bai ban bao bar bau bba bbb bbi bbn bbo bbr bbu bi- bia bib bii bin bio bir biu bna bnb bni bnn bno bnr bnu boa bob boi bon boo bor bou bra brb bri brn bro brr bru bua bub bui bun buo bur buu ia- iaa iab iai ian iao iar iau iba ibb ibi ibn ibo ibr ibu iia iib iii iin iio iir iiu in- ina inb ini inn ino inr inu io- ioa iob ioi ion ioo ior iou ir- ira irb iri irn iro irr iru iu- iua iub iui iur n-i naa nab nai nan nao nar nau nba nbb nbi nbn nbo nbr nbu nia nib nii nin nio nir niu nna nnb nni nnn nno nnu no- noa nob noi non noo nor nou nra nrb nri nrn nro nrr nru nua nub nui nun nuo nur nuu o-i oaa oab oai oan oao oar oau ob- oba obb obi obn obo obr obu oia oib oii oin oio oir oiu on- ona onb oni onn ono onr onu oo- ooa oob ooi oon ooo oor or- ora orb ori orn oro orr oru ou- oua oui oun ouo our ra- raa rab rai ran rao rar rau rba rbb rbi rbn rbo rbr rbu ria rib rii rin rio rir rna rnb rni rnn rno rnr rnu roa rob roi ron roo ror rou rra rrb rri rrn rrr rru rua rub rui run ruo rur ruu ua- uaa uab uai uan uao uar uau uba ubb ubi ubn ubo ubr ubu uia uib uii uin uio uir uiu un- una unb uni unn uno unr unu uoa uob uon uoo uor ur- ura urb uri urn uro urr uru uua uun uur uuu