Institutes' rhymes with:
constitutes, institutes, prostitutes, substitutes, absolutes, attributes, bandicoots, constitutes, executes, grapefruits, institutes, jumpsuits, lawsuit's, lawsuits, offshoots, pantsuits, parachutes, persecutes, prosecutes, prostitutes, spacesuits, substitutes, swimsuits
Institutes' sounds like:
incata's, incestuous, incites, inequities, ingots, injects, injudicious, injustice, injustices, inkatha's, insect's, insects, insides, insidious, insights, insists, institute's, institutes