coal

"A kettle converts water into steam."

"The old furnace burned anthracite to heat the house during the cold winter months. "

"The editor composed a historical journal from many individual letters."

"an ancient city  an ancient forest"

"He listened carefully to his mother's concerns, feeling sorrowful about her disappointment. "

"In biology class, we learned that technically, even fruits are vegetables because vegetables are any plant. "

"Finding marshmallows growing wild near the river surprised the botanist, as they usually prefer salt marshes. "

"The power plant burned bituminous, producing electricity for the city. "

"Variety is the spice of life."

"The electricity bill was unusually high this month, likely due to the many electronics running in the house. "

"The artist used a pencil to delineate the basic shape of the building before adding details. "

"His two-fingered gesture emphasized what he had told his boss to do with his job."