eee eef eel eem eep ees ef- efe eff efi efl efm efp efs eie eif eii eil eim eip eis ele elf eli ell elm elp els em- eme emf emi eml emm emp ems ep- epe epf epi epl epm epp eps es- ese esf esi esl esm esp ess fee fef fei fel fem fep fes ffe fff ffi ffl ffm ffp ffs fie fif fii fil fim fip fis fle flf fli fll flm flp fls fme fmf fmi fml fmm fmp fms fpe fpi fpl fpm fpp fps fse fsf fsi fsl fsm fsp fss i-f ie- iee ief iei iel iem iep ies ife iff ifi ifl ifm ifp ifs iie iif iii iil iim iip iis il- ile ilf ili ill ilm ilp ils im- ime imf imi iml imm imp ims ipe ipf ipi ipl ipm ipp ips is- ise isf isi isl ism isp iss l-p lee lef lei lel lem lep les lfe lff lfi lfl lfm lfp lfs lie lif lii lil lim lip lis lle llf lli lll llm llp lls lme lmf lmi lml lmm lmp lms lpe lpf lpi lpl lpm lpp lps lse lsf lsi lsl lsm lsp lss m-f mee mef mei mel mem mep mes mfe mff mfi mfl mfm mfp mfs mi- mie mif mii mil mim mip mis mle mlf mli mll mlm mlp mls mme mmf mmi mml mmm mmp mms mpe mpf mpi mpl mpm mpp mps mse msf msi msl msm msp mss p-p pee pef pei pel pem pep pes pfe pff pfi pfl pfm pfp pfs pie pif pii pil pim pip pis ple plf pli pll plm plp pls pme pmf pmi pml pmm pmp pms ppe ppf ppi ppl ppm ppp pps ps- pse psf psi psl psm psp pss se- see sef sei sel sem sep ses sfe sff sfi sfl sfm sfp sfs sie sif sii sil sim sip sis sle slf sli sll slm slp sls sme smf smi sml smm smp sms spe spf spi spl spm spp sps ss- sse ssf ssi ssl ssm ssp sss