a-a a-b a-i aaa aab aai aao aau ab- aba abb abi abo abu ai- aia aib aii aio aiu aoa aob aoi aoo aou au- aua aub aui auo b-u baa bab bai bao bau bba bbb bbi bbo bbu bi- bia bib bii bio biu boa bob boi boo bou bua bub bui buo buu ia- iaa iab iai iao iau iba ibb ibi ibo ibu iia iib iii iio iiu io- ioa iob ioi ioo iou iu- iua iub iui o-i oaa oab oai oao oau ob- oba obb obi obo obu oia oib oii oio oiu oo- ooa oob ooi ooo ou- oua oui ouo ua- uaa uab uai uao uau uba ubb ubi ubo ubu uia uib uii uio uiu uoa uob uoo uua uuu