a-a aaa aao aas aau aax aay aoa aoo aos aou aox as- asa aso ass asu asx asy au- aua auo aus aux ax- axa axo axs axx ay- aya ayo ays ayu ayx oaa oao oas oau oax oo- ooa ooo oos oox os- osa oso oss osu osx ou- oua ouo ous ox- oxa oxo oxx oxy oya oyo oys saa sao sas sau sax say soa soo sos sou sox soy ss- ssa sso sss ssu ssx sua suo sus suu sux suy sxs sxu sy- sya sys syu syx ua- uaa uao uas uau uay uoa uoo uos uox usa uso uss usu usx uua uus uuu uxo uxu uyo uys uyu xaa xas xau xoa xoo xos xox xsa xss xus xxo xxx xxy xyy yaa yao yas yau yax yay yoo yos you yox yoy ysa yso yss ysu ysy yua yuo yus yuu yux yuy yxa yxy yys yyu yyy