Serial:
* He was a fan of the classic TV serial "The Twilight Zone." (referring to a television series)
* The detective worked tirelessly to solve the serial murders in the city. (referring to a series of crimes)
* She wrote a serial novel that was published in installments. (referring to a story published in parts)
Cereal:
* I eat a bowl of cereal every morning for breakfast. (referring to a breakfast food)
* The cereal aisle at the grocery store was packed with colorful boxes. (referring to the breakfast food section)
* He accidentally spilled his cereal all over the floor. (referring to an action with the breakfast food)