Simple past tense and past participle of smolder.(verb)
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Use "smoldered" in a sentence
"The death-like eyes of a dozen laser lenses stared back at him, and around him the bodies of Janice, Luke and Morgan still smoldered from the lethal burns. “Why? †he whispered, his voice wavering as he struggled to hold his shaking hand still. “Why did you do this? †“Samuel, †she answered, her voice like cold wind chimes within the hollow tomb that the chamber had become. “You know I did this … I did all this for you."
"She walked through streets where buildings still smoldered to reach the clinic, which had been destroyed."
"In dozens of cities, empty shells of destroyed buildings were clouded with smoke from fires that still smoldered."