ROUNDTRIPS

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din dip dis dit don dor dos dot dui dun duo dup ids ins ion its nip nit nod nor nos not nus nut ods ons ops opt ors ort oud our out pin pis pit piu pod poi pot pro psi pst pud pun pur pus put rid rin rip rod rot run rut sin sip sir sit sod son sop sot sou sri sun sup tin tip tis tod ton top tor tui tun tup udo uns upo ups urd urn urp uts

dino dins dint dips dipt dirt dits doit dons dorp dorr dors dost dots dour drip drop duit duns dunt duos dups durn duro durr dust inro into ions iron nips nits nodi nods noir nori nous nurd nuts onus opts opus orts ouds ours oust outs pins pint pion pirn piso pits pods pois pond pons porn port post pots pour pout prod pros ptui puds puns punt puri purr purs puts rids rind rins riot rips rods roti rots roup rout ruin runs runt rust ruts snip snit snot sord sori sorn sort soup sour spin spit spot spud spun spur stir stop stud stun suit surd tins tips tiro tods tons topi tops tori torn torr tors tour trio trip trod trop tuis tuns tups turd turn udon udos undo unit unto updo upon urds urns urps