Here's what rhymes with certify.
high thy vi hi shy sigh fi hy thigh vie psi hai cy fy sy thei phi by my why die lie y buy fly sky guy satisfy tie modify bi bye chi defy dye nigh pi pie spy thai dei fry ly quae rye sly ty wir awry lye mai muy nai ratify wry kai lai luy mei tai wai edify sty bonsai deify ossify stye turfy versify slier apply dry try cry deny justify verify butterfly gratify notify ply underlie alibi amplify nullify pacify pry tri trie belie pri terrify typify untie codify mollify ramify acidify aquae spry stratify stultify amebae horrify lanai mummify shanghai vitrify beatify speechify banzais dandify yuppify supply thereby occupy rely hereby qualify specify alkali classify signify simplify testify purify diversify fortify magnify rectify samurai unify decry falsify lullaby pupae solidify amoebae descry dignify overlie personify vilify firefly mystify ultrahigh vivify blowfly calcify petrify stupefy dissatisfy overfly scarify scurfy barfly hyperbolae prettify overbuy identify reply imply nearby whereby clarify comply multiply glorify goodbye quantify alveoli standby beautify termini crucify liquefy mortify oversupply retry triply emulsify reunify liquify drachmai refortify ripply syllabify stimuli nuclei exemplify intensify disqualify indemnify objectify resupply demystify detoxify dragonfly electrify misapply revivify declassify gentrify solemnify oversimplify preoccupy reclassify misidentify cumuli transmogrify