Students should understand that affixes are groups of letters that are added to the beginning or end of a word to change the word's meaning. Prefixes are a type of affix added to the beginning of a word to alter its meaning or, in some cases, to create an entirely new word. For example, the word aparecer means “to become visible”. When students add the prefix re- (which implies the repetition of an action) to the beginning of aparecer (base word), the meaning of reaparecer is “to be visible again.” Suffixes are affixes added to the ends of words to alter the meaning or create a new word. Suffixes can indicate the part of speech the word functions as. For example, the word lentísimo consists of the suffix -ísimo (which makes the superlative form of adjectives) combined with the base word lento (slow). Thus, the word lentísimo means "in an extremely slow way”. Recognizing affixes and understanding the specific changes they bring to a base word can help students to decode and process unfamiliar words as well as to manipulate and construct words of their own.