sbd sbe sbg sbi sbk sbm sbn sbo sbr sbs sca scb scc scd sce scg sci sck scm scn sco scr scs sda sdb sdc sdd sde sdg sdi sdk sdm sdn sdo sdr sds se- sea seb sec sed see seg sei sek sem sen seo ser ses sga sgb sgc sgd sge sgg sgi sgk sgm sgn sgo sgr sgs sia sib sic sid sie sig sii sik sim sin sio sir sis sk- ska skb skc skd ske skg ski skk skm sko skr sks sma smb smc smd sme smg smi smk smm smn smo smr sms sna snb snc snd sne sng sni snk snm snn sno snr sns soa sob soc sod soe sog soi sok som son soo sor sos sr- sra srb src srd sre srg sri srk srm srn sro srr srs ss- ssa ssb ssc ssd sse ssg ssi ssk ssm ssn sso ssr sss