sealant

"The old plumber worked with lead pipes in the school's plumbing system. "

"After a long day at work, Sarah relaxed in the bathtub. "

"The smooth surface of the kitchen table was perfect for setting the dinner plates. "

"Asphalt, composed of oil and sand, is a widely used material for roads."

"The new math strategies were applied successfully in the classroom. "

"Plastic bottles are made from polymers, which are long chains of smaller molecules linked together. "

"I saw a movement in that grass on the hill."

"The colors of autumn leaves come from different pigments in the tree cells as the green chlorophyll fades. "

"I brush my teeth regularly to prevent them from turning yellow."

"The moderates are the natural advocates of ecumenism against the fanatics of their churches."

"She struggled to play the difficult passages."

"He never expected to be discovered."