Based on Brown (1973)
| Grammatical Morpheme | Example |
|---|---|
| Present progressive (-ing) | Baby crying. |
| in | Juice in cup. |
| on | Book on table. |
| Plural regular (-s) | Daddy have tools. |
| Past irregular | Doggie ate bone. |
| Possessive ('s) | Jake's apple. |
| Uncontractible copula (used as main verb) | This is mine. |
| Articles (a, the) | A red apple.
The big house. |
| Past regular (-ed) | He jumped high. |
| Third person regular (-s) | Susie drinks. |
| Third person irregular | Baby does patty-cake.
Kitty has a toy. |
| Uncontractible auxiliary | Are you thirsty?
She was running. He is. (Response to “Who’s crying?”) |
| Contractible copula | It's cold outside. |
| Contractible auxiliary | Mommy's crying. |
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*All grammatical morphemes are typically acquired by about 4 years of age. Brown, R. (1973). A first language: The early stages. Cambridge, MA: Harvard University Press. |
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