fff ffi ffm ffs fft fif fii fim fis fit fmf fmi fmm fms fmt fsf fsi fsm fss fst ftf fti ftm fts ftt i-f iff ifi ifm ifs ift iif iii iim iis iit im- imf imi imm ims imt is- isf isi ism iss ist itf iti itm its itt m-f mff mfi mfm mfs mft mi- mif mii mim mis mit mmf mmi mmm mms mmt msf msi msm mss mst mtf mti mtm mts mtt sff sfi sfm sfs sft sif sii sim sis sit smf smi smm sms smt ss- ssf ssi ssm sss sst stf sti stm sts stt tff tfi tfm tfs tft tif tii tim tis tit tmf tmi tmm tms tmt tsf tsi tsm tss tst ttf tti ttm tts ttt