bbb bbi bbo bbs bbt bi- bib bii bio bis bit biv bob boi boo bos bot bov bsb bsi bso bss bst bsv btb bti bto bts btt btv bvb bvi bvo bvs bvt bvv i-v ibb ibi ibo ibs ibt ibv iib iii iio iis iit io- iob ioi ioo ios iot iov is- isb isi iso iss ist isv itb iti ito its itt itv ivb ivi ivo ivs ivt ivv o-i ob- obb obi obo obs obt obv oib oii oio ois oit oiv oo- oob ooi ooo oos oot oov os- osb osi oso oss ost osv ot- otb oti oto ots ott otv ov- ovb ovi ovo ovs ovv sbb sbi sbo sbs sbt sbv sib sii sio sis sit siv sob soi soo sos sot sov ss- ssb ssi sso sss sst ssv stb sti sto sts stt stv svb svi svo svs svt svv tbb tbi tbo tbs tbt tbv tib tii tio tis tit tiv to- tob toi too tos tot tov tsb tsi tso tss tst tsv ttb tti tto tts ttt ttv tvb tvi tvo tvs tvt vbi vbo vbs vbv vi- vib vii vio vis vit viv vob voi voo vos vot vov vsb vsi vso vss vst vsv vtb vti vto vts vtt vtv vvb vvi vvo vvs vvt vvv