Firefighters' boots crunched on charred ground.
Meaning: The firefighters were walking on the burned ground, and their boots were making a crunching sound.
Choice of Words: Firefighters are people who work to put out fires. Boots are sturdy shoes that protect the feet. Crunched means to make a crackling sound when you step on something. Charred means burned and blackened. Ground is the solid surface of the Earth.
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