SUBSTRUCTION

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bins bint bios biro bits bitt born bort boss bots bott bout brin brio bris brit bros brut buns bunt burn burs buss bust buts butt cion cist cobs coin coir coni cons corn cors coss cost cots crib cris crit crus cubs cunt curb curn curs curt cuss cuts icon inro into ions iron nibs nits nobs noir nori nous nubs nuts obis obit onus orbs orcs orts otic ours oust outs ribs rins riot robs rocs roti rots rout rubs ruin runs runt rust ruts scot scut sibs sics sins sirs sits snib snit snob snot snub sobs sons sorb sori sorn sort sots sour sous sris stir stob stot stub stun subs suit suns tics tins tint tiro tits toit tons torc tori torn tors tort toss tost tots tour tout trio trot tubs tuis tuns turn tuts tutu unci unco unit unto urbs uric urns urus