selenium

"The student used a microscope to see the tiny cells in the plant leaf. "

"The new school principal is a powerful advocate for student success. "

"The computer chip relies on semiconductors to conduct electricity efficiently. "

"Letters are the elements of written language."

"The police identified the thief using security camera footage. "

"We could color the walls red."

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

"The town's economy depended on glassmaking for many years, with families passing down the techniques from generation to generation. "

"The process of baking a cake involves several steps, from mixing the ingredients to putting it in the oven. "

"The family-owned factory in China handled the export of toys to many countries. "

"The scientist studied the effects of different types of soil on plant growth. "

"The scientist studied the chemical composition of the soil sample. "