The document discusses prefixes and suffixes. Prefixes are added to the beginning of words to change their meaning, while suffixes are added to the end of words. Examples are given of common prefixes like "pre-", "im-", "bi-", and "non-" and suffixes like "-less", "-ful", and "-er". The root word is the base word that prefixes and suffixes are added to in order to form new words. Students are provided examples of analyzing words to determine their root words and links to online games to practice adding prefixes and suffixes.