-er -ic a-a a-b a-c a-i a-t aaa aab aac aae aai aak aar aat ab- aba abb abc abe abi abk abr abt ac- aca acb acc ace aci ack acr act aea aeb aec aee aei aek aer aet ai- aia aib aic aie aii aik air ait aka akb akc ake aki akk akr ar- ara arb arc are ari ark arr art at- ata atb atc ate ati atr att baa bab bac bae bai bak bar bat bba bbb bbc bbe bbi bbk bbr bbt bca bcb bcc bce bci bck bcr bct be- bea beb bec bee bei bek ber bet bi- bia bib bic bie bii bik bir bit bka bkb bkc bke bkk bkr bkt bra brb bre bri brk brr brt bta btb btc bte bti btk btr btt c-- caa cab cac cae cai cak car cat cba cbb cbc cbe cbi cbk cbr cbt cca ccb ccc cce cci cck ccr cct ce- cea ceb cec cee cei cek cer cet ci- cia cib cic cie cii cik cir cit cka ckb ckc cki ckt cra crb crc cre cri crk crr crt cta ctb ctc cte cti ctk ctr ctt eaa eab eac eae eai eak ear eat eba ebb ebc ebe ebi ebk ebr ebt ec- eca ecb ecc ece eci eck ecr ect eea eeb eec eee eek eer eet eia eib eic eie eii eik eir eit eka ekb ekc eke eki ekr ekt era erb erc ere eri erk err ert eta etb etc ete eti etk etr ett ia- iaa iab iac iae iai iar iat iba ibb ibc ibe ibi ibk ibr ibt ica icb icc ice ici ick icr ict ie- iea iec iee iei iek ier iet iia iib iic iie iii iir iit ika ikb ikc ike iki ikk ikr ikt ir- ira irb irc ire iri irk irr irt ita itb itc ite iti itk itt k-t ka- kaa kab kac kae kai kak kar kat kba kbb kbc kbe kbi kbk kbr kca kcb kcc kce kci kck kcr kct ke- kea keb kec kee kei kek ker ket kia kib kic kie kii kik kir kit kkb kkc kke kki kkk kkr kkt kra krc kri krk krr krt kta ktb ktc kte ktk ktr ktt ra- raa rab rac rae rai rak rar rat rba rbb rbc rbe rbi rbk rbr rbt rca rcb rcc rce rci rcr rct re- rea reb rec ree rei rek rer ret ria rib ric rie rii rik rir rit rkb rkc rke rkk rkt rra rrb rrc rri rrk rrr rrt rta rtb rtc rte rti rtk rtr rtt taa tab tac tae tai tak tar tat tba tbb tbc tbe tbi tbk tbr tbt tca tcb tcc tce tci tck tcr tct te- tea teb tec tee tei tek ter tet tia tib tic tie tii tik tir tit tka tkb tkc tke tkk tkr tkt tra trb trc tre tri trk trr trt tta ttb ttc tte tti ttk ttr ttt