-er -up ddd dde ddp ddr dds ddu de- ded dee dep der des deu dpd dpe dpp dpr dps dpu drd dre drp drr drs dru dsd dse dsp dsr dss dsu dud due dup dur dus ed- edd ede edp edr eds edu eed eee eep eer ees ep- epd epe epp epr eps epu erd ere erp err ers eru es- esd ese esp esr ess esu eu- eud eue eup eur eus p-p pdd pde pdp pdr pds pdu ped pee pep per pes peu ppd ppe ppp ppr pps ppu prd pre prp prr prs pru ps- psd pse psp psr pss psu pud pue pup pur pus puu rdd rde rdp rdr rds rdu re- red ree rep rer res reu rpd rpe rpp rpr rps rpu rrd rrp rrr rrs rru rsd rse rsp rsr rss rsu rud rue rup rur rus ruu sdd sde sdp sdr sds sdu se- sed see sep ser ses seu spd spe spp spr sps spu sr- srd sre srp srr srs ss- ssd sse ssp ssr sss ssu sud sue sup sur sus suu udd ude udp udr uds udu ued uee uep uer ues up- upd upe upp upr ups upu ur- urd ure urp urr urs uru usd use usp usr uss usu uue uur uus uuu