-th c-- ccc cch cck cco ccs cct ch- chc chh chk cho chs cht ckc ckh cko cks ckt co- coc coh cok coo cos cot csc csh csk cso css cst ctc cth ctk cto cts ctt hcc hch hck hco hcs hct hhc hhh hhk hho hhs hht hkh hkk hko hks hkt hoc hoh hok hoo hos hot hsc hsh hsk hss hst htc hth htk hto hts htt k-t kcc kch kck kcs kct khh khk kho khs kkc kkh kkk kks kkt koc koh kok koo kos kot ksc ksh ksk kso kss kst ktc kth ktk kto kts ktt oc- occ och ock oco ocs oct ohc ohh oho ohs oht okc okk oko oks oo- ooc ooh ook ooo oos oot os- osc osh osk oso oss ost ot- otc oth otk oto ots ott scc sch sck sco scs sct sh- shc shh shk sho shs sht sk- skc skh skk sko sks skt soc soh sok soo sos sot ss- ssc ssh ssk sso sss sst stc sth stk sto sts stt tcc tch tck tco tcs tct th- thc thh thk tho ths tht tkc tkk tko tks tkt to- toc toh tok too tos tot tsc tsh tsk tso tss tst ttc tth ttk tto tts ttt