Which suffix is commonly listed among Brown's 14 Morphemes?

• A. -ly
• B. -able
• C. -ed
• D. -ment

Answer: (C)

The main idea here is understanding Brown’s list of early grammatical markers that children tend to acquire. Among those early morphemes, the suffix -ed marks past tense on regular verbs, and it’s one of the most consistently observed inflectional morphemes Brown identified. It’s frequent in everyday speech and a straightforward way to indicate that an action happened in the past, so children often learn it early.

The other suffixes are not typically highlighted as Brown’s morphemes. -ly turns adjectives into adverbs, which is a derivational change rather than a simple tense or number marker. -able and -ment also create new word forms (deriving adjectives or nouns from other bases), rather than signaling grammatical tense or agreement. These kinds of derivational suffixes aren’t the focus of Brown’s original list, which centers on more basic, inflectional structures like -ing and -ed, as well as a few essential function words.