What are affixes in linguistics?

Affixes in linguistics refer specifically to syllables or groups of letters that attach to a base word to modify its meaning or create new words. They can be prefixes, which come at the beginning of a word, or suffixes, which are added to the end. For example, in the word "unhappiness," "un-" is a prefix that modifies the root word "happy," altering its meaning to convey the opposite. This ability to change the meaning of a word or to form new words is a key function of affixes, making them an essential part of morphology in language studies.

The other choices do not accurately describe affixes. For instance, the idea of ambiguous meanings relates more to semantics than to the structural aspect of how words are formed. Parts of speech that remain unchanged refers to grammatical categories rather than morphological elements linked to words. Vowel combinations in a word are unrelated to the concept of affixes, which is centered around meaningful modifications to words rather than specific sounds or letters.