Simple past tense and past participle of deepen.(verb)
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Use "deepened" in a sentence
"The expression deepened the sun-creased lines splaying from the corners of his eyes."
"The expression deepened the lines in his face; that made me wonder if it was a look I had often worn without being aware of it."
"As a natural contrarian, Orwell's distrust of the Left's hero worship of dictators like Stalin deepened after his personal experience in the Spanish Civil War where he saw Communism betray his view of the revolution."