PROTOHISTORY

hi ho is it oh oi op or os oy pi sh si so ti to yo

hip his hit hop hos hot hoy hyp its oho ohs ooh oot ops opt ors ort phi pht pis pit poh poi poo pot pro pry psi pst rho rip rot shy sip sir sit sop sot soy spy sri sty tho thy tip tis tit too top tor tot toy try yip

hips hist hits hoop hoot hops host hots hoys hypo hyps oohs oops oots opts orts otto phis phot pish piso pith pits pity pois pooh poor poos port posh post posy pots pros pyro rhos riot rips root ropy rosy roti roto rots ryot ship shit shoo shop shot shri sith soot soph sori sort soth spit spot spry stir stop stot syph thio thir this thro tips tiro tits toit toot toph topi topo tops tori toro torr tors tort tory tosh tost tots toyo toys trio trip trop trot troy typo tyro yips yirr