Third-person singular simple present indicative form of chalk.(verb)
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Use "chalks" in a sentence
"When Myra asked her, Ginny went and got the sidewalk chalks from the childrens 'art case."
"While America's counterintelligence team chalks up some victories, Mr. Wise portrays it as powerless to plug thousands of security lapses that allow an army of Chinese spies to carry off secret information."
"But Cary assures viewers his series is still vital and chalks the issue up to tricky scheduling."