Based on Brown (1973)
|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.|
*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.