-er a-a a-c a-t aaa aac aad aae aar aat ac- aca acc acd ace acr act ad- ada adc add ade adr adt aea aec aed aee aer aet ar- ara arc ard are arr art at- ata atc atd ate atr att c-- caa cac cad cae car cat cca ccc ccd cce ccr cct cda cdc cdd cde cdr cdt ce- cea cec ced cee cer cet cra crc crd cre crr crt cta ctc ctd cte ctr ctt daa dac dad dae dar dat dca dcc dcd dce dcr dct dda ddc ddd dde ddr ddt de- dea dec ded dee der det dra drc drd dre drr drt dta dtc dtd dte dtr dtt eaa eac ead eae ear eat ec- eca ecc ecd ece ecr ect ed- eda edc edd ede edr edt eea eec eed eee eer eet era erc erd ere err ert eta etc etd ete etr ett ra- raa rac rad rae rar rat rca rcc rcd rce rcr rct rda rdc rdd rde rdr rdt re- rea rec red ree rer ret rra rrc rrd rrr rrt rta rtc rtd rte rtr rtt taa tac tad tae tar tat tca tcc tcd tce tcr tct tda tdc tdd tde tdr tdt te- tea tec ted tee ter tet tra trc trd tre trr trt tta ttc ttd tte ttr ttt