What are morphemes?

• A. The smallest units of meaning in words, including roots, prefixes, and suffixes.
• B. A type of punctuation used to indicate tone.
• C. A sentence's main subject and verb.
• D. A group of words that expresses a complete thought.

Answer: (A)

Morphemes are the smallest units of meaning in language. They include roots that carry core semantic content and affixes—prefixes and suffixes—that modify meaning or grammar. Some morphemes can stand alone as words (free morphemes like cat or book), while others must attach to other morphemes (bound morphemes like un-, -s, or -ed). By combining morphemes, we build words and convey tense, number, negation, and more. For example, in cats there are two morphemes: cat plus the plural marker s. In unbelievable, there’s un- (negation) plus believe plus -able (capable of). The other options describe punctuation, or sentence structure, which aren’t about the smallest meaningful units of language.