Run-hot-and-cold Definition

verb
(idiomatic) To alternate between two opposite extremes, such as enthusiasm and disinterest or success and failure.
Henrietta's feelings for Delbert run hot and cold--one minute she's hopelessly in love with him, and the next she can't stand the sight of him.
The business runs hot and cold; some months our firm doesn't earn enough to cover expenses and other months, we net 400% profits.
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