Chalk & Cheese

CHALK AND CHEESE - "(U.S. equivalent) 'night and day.' Worlds apart. As different as chalk from cheese is the usual phrase, the equivalent of 'as different as night and day.' This is sometimes shortened to 'chalk and cheese': 'Why, they're as different as chalk and cheese." From "British English: A to Zed" by Norman W. Schur (Harper Perennial, New York, 1987).

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