Morphological development

Brown's stage 1 I

12-26 months

About 50 words in vocabulary

Basic phrases (with communicative intent)

"more juice" "my doll"

Brown's stage 2 II

27-30 months

Present progressive -ing "man running"

"in" and "on" "in house" "on book"

Regular plural -s "my kids"

Brown's stage 3 III

Irregular past tense "me drew"

Possessive 's "daddy's hat"

Uncontractible copula "he is sick"

Brown's stage 4 IV

35-40 months

Articles (a, the) "the bucket"; "a drink"

Regular past tense "she shopped"

Third person regular present tense "he runs"

Browns stage 5 V

Third person irregular "doggy does tricks"

Uncontractible auxiliary "He was jumping"

Contractible copula "She's happy"

Contractible auxiliary "She's dancing"

Copula

A connecting word, particulary the verb BE connecting a subject and a complement

Describe internal state or identity

Acts as an equal sign Bob is happy -> Bob = happy

Compliment of this is mostly a noun or adjective

auxillary

helping verbs (do, be, have) support a main verb

Auxillary shows tense, aspect, or mood

Bob HAS gone or Bob IS running

Compliment of this is always a verb

Mean length of utterance (MLU) formula

Total number of MORPHEMES/Total number of UTTERANCES

12-26 months MLU (1:0-2:2)

1.0-2.0

27-30 months MLU (2:3-2:5)

2.0-2.5

31-34 months MLU (2:6-2:10)

2.5-3.0

35-40 months MLU (2:11-3:4)

3.0-3.75

41-46 months MLU (3:5-3:10)

3.75-4.5

47+ months MLU (3:8+)

4.5+