THESAURUS
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afford proof of, ascertain, assure, balance, ballast, bring home to, certify, cinch, clear up, clinch, counterbalance, decide, demonstrate, determine, dismiss all doubt, ensure, establish, find out, firm, firm up, fix, follow, follow from, freeze, get at, have a case, hold, hold good, hold water, immobilize, insure, keep, make certain, make good, make no doubt, make no mistake, make out, make sure, make sure of, pin down, prove, prove to be, prove true, reassure, remove all doubt, retain, see that, see to it, set at rest, settle, settle the matter, show, sort out, stabilitate, stabilize, steady, stick, transfix