Third-person singular simple present indicative form of toughen.(verb)
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Use "toughens" in a sentence
"Those findings grabbed attention of policymakers and the media: a bill called the "Paycheck Fairness Act," which toughens employers ` legal responsibility to eliminate gender discrimination, is about to be introduced in the U.S. Senate."
"The focus on pay comes as the U.K.'s financial regulator, the Financial Services Authority, toughens its stance on bank bonuses."
"The DIAL test also gave the EPA support for its determination that Tonawanda Coke should be classified as a "major" source of benzene, which toughens its pollution control requirements."