a-ii aaaa aaab aaai aaar aaba aabb aabi aaib aaii aaoo aara aari aaro aaru abaa abab abai abar abau abb- abba abbb abbi abbo abbr abia abib abir abiu aboa abob aboo abor abou abra abri abro abua aiai aiba aibo aiia aiib aiir aioi aira airi airo aiui aoba aora aorb arab arai arar arau arba arbi aria arib arii ario aroa arob aroi aroo aror arr- arra arri arro arrr arru arua arub arui auaa aur- aura auri auro ba-i baaa baar baba babb babi babo babr babu baia baib baio bair bar- bara barb bari baro barr baru bau- baur bbau bbbb biao biar biba bibb bibi bibo bio- bioi biou bira birb biri biro birr biru boab boai boar boba bobb bobi bobo bobu boi- boii boiu boob boor bor- bora bori boro borr boru boua bour brab brai brao brau bria brio broa brob broo bror brou brrr buar buba bubb bubi bubo bubu buir buiu bur- bura burb buri buro burr buru iaaa iaai iaba iaia iara iaru ibar ibia ibra ibri ibro iiii iiio iioi iioo iira ioba iobi ioii ioio iooi iooo iora iori irai irao irar iri- iria irio irob irra irri iuiu iura oaau oara obai obba obbo obia oboi obor obra obri obro oiba oiii oira ooaa ooba oobi ooia oooo oora orab orai orao orar orba orbb orbi orbo orbu ori- oria orio oro- oror orra orri orro orub ouii ouir our- oura ouro ouu- raab raba rabb rabi rabo rabu raia raii rair raiu raob rara rarb rari raro raua raub rbbb rbbr riaa riab riai riau rib- riba ribo ribu riia riou riri roab roar rob- roba robb robi robo robu roia roio roir roiu roob rooi roor rora rori roro roru roua roub rrrr ruba rubb rubi rubu rura ruri ruro ruru uair uaru uaua ubar ubba ubbi ubbo ubii ubir ubra uira uirr uor- urai urao urau urba urbi uria urib uriu uro- uroa uroo urra urri urur uuri uuuu