a-a a-b a-i aaa aab aad aai aao ab- aba abb abd abi abo ad- ada adb add adi ado ai- aia aib aid aii aio aoa aob aod aoi aoo baa bab bad bai bao bba bbb bbd bbi bbo bda bdb bdd bdi bdo bi- bia bib bid bii bio boa bob bod boi boo daa dab dad dai dao dba dbb dbd dbi dbo dda ddb ddd ddi ddo di- dia dib did dii dio doa dob dod doi doo i-d ia- iaa iab iad iai iao iba ibb ibd ibi ibo ida idb idd idi ido iia iib iid iii iio io- ioa iob iod ioi ioo o-i oaa oab oad oai oao ob- oba obb obd obi obo oda odb odd odi odo oia oib oid oii oio oo- ooa oob ood ooi ooo