Third-person singular simple present indicative form of foil.(verb)
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Use "foils" in a sentence
"The use of foils is a literary device for enhancing the traits of one character by contrasting them with the totally opposite traits of another."
"She constructed a device for sending alpha particles emitted from radium C to the scintillation screen through thin foils of gold or of copper which acted as primary absorbers for the ordinary a-particles. 53 35"
"The showrunner's ADD continually causes them to plow through potentially long-term foils for Jack with shocking speed."