* Formal: "The skeptic remained unconvinced by the evidence presented, demanding further proof before accepting the theory."
* Informal: "Despite the glowing reviews, I remain a skeptic about the new restaurant. I've heard mixed things."
* Figurative: "Her unwavering faith in her abilities made her a skeptic of any advice that suggested otherwise."
* Direct: "My grandfather is a skeptic who doesn't believe in anything he can't see."
* With a negative connotation: "He was such a skeptic that he refused to even consider the possibility of a solution."
Remember, "skeptic" can be used as a noun or an adjective.