What is a suffix?

A suffix is defined as a group of letters added at the end of a base word to modify its meaning or grammatical function. For example, the base word "help" can become "helpful" when the suffix "-ful" is added, altering its meaning from a verb to an adjective. This transformation enhances the base word, allowing for greater expression and clarity in language.

In contrast, the first option describes a prefix, which is added to the beginning of a word, and the third option refers to a root word without any modifications, missing the concept of added elements that change meaning. The fourth option incorrectly equates suffixes with prefixes, which are distinct in their placement within a word and their function in modifying meanings. Thus, recognizing a suffix as a meaningful addition at the end of a base word is essential for understanding word formation and expansion in language.