-er -ey bbb bbe bbo bbr bbt bbx bby be- beb bee beo ber bet bex bey bob boe boo bor bot box boy brb bre bro brr brt brx bry btb bte bto btr btt btx bty bxb bxo bxx by- bye byo byr byt ebb ebe ebo ebr ebt ebx eby eeb eee eeo eer eet eex eey eo- eob eoe eoo eor eot erb ere ero err ert ery etb ete eto etr ett etx ety ex- exe exo exr ext exx exy eye eyo eyr eyt ob- obb obe obo obr obt obx oby oeb oee oeo oer oet oex oey oo- oob ooo oor oot oox or- orb ore oro orr ort orx ory ot- otb ote oto otr ott ox- oxb oxo oxt oxx oxy oye oyo rbb rbe rbo rbr rbt rbx re- reb ree reo rer ret rex rey rob roe roo ror rot rox roy rrb rrr rrt rtb rte rto rtr rtt rtx rty rxr ry- rye ryo ryr ryy t-x tbb tbe tbo tbr tbt te- teb tee teo ter tet tex tey to- tob toe too tor tot tox toy trb tre tro trr trt trx try ttb tte tto ttr ttt ttx tty txe txt tye tyo tyr tyt xbe xbr xbx xee xer xet xex xoo xor xot xox xrt xrx xry xtr xtx xty xxo xxx xxy xyr xyy ybe ybr yby yeb yee yeo yer yet yex yey yob yoe yoo yor yot yox yoy yre yro yrt yte yto ytr ytt yxe yxy yyb yye yyt yyy