Child Language Development: Semantic Roles, Morphemes, and MLU Stages

Semantic Role Codes

Categories used to describe how words function in early child sentences (agent, action, object, etc.)

Agent

The person or thing performing an action

Action

The activity being performed in a sentence

Object

The person or thing receiving the action

Experiencer

The person experiencing a feeling or perception

Entity

The object or thing being referred to in a sentence

Locative

Indicates location or place

Demonstrative

Words that point to something (this, that, these, those)

Recurrence

Indicates something happening again (ex: more juice)

Possessor

Shows ownership (ex: mom's hat)

Recipient

The person receiving something

Attribute

Describes a property or quality of something

Negation

Expressing "no" or "not"

Brown's Stages

Developmental stages describing how children acquire grammatical morphemes

Grammatical Morphemes

Small units of language that modify meaning or grammatical function (ex: plural -s, past tense -ed)

Obligatory Grammatical Context

Situations where grammar rules require a specific morpheme

Criterion for Mastery (Miller 1981)

A child correctly uses a grammatical morpheme 90% of the time

MLU (Mean Length of Utterance)

The average number of morphemes per utterance used to estimate language development

Importance of MLU

Reflects growing structural complexity in children's language and helps guide treatment

How to Calculate MLU

Divide total number of morphemes by the number of utterances

MLU Stage I

One-word and two-word combinations; mostly single syllable words

MLU Stage II

Emergence of grammatical morphemes and early pronouns like I, it, this, that

MLU Stage III

Expanded pronouns, helping verbs begin appearing, vocabulary about 1200 words

MLU Stage IV

More complex sentences, multi-clause structures, vocabulary about 1500 words

MLU Stage V

Clause conjunctions, primitive tag questions, vocabulary about 1900 words

Plural Morpheme

Indicates more than one item (cars, hats, dishes)

Possessive Morpheme

Shows ownership (mom's hat)

3rd Person Singular Morpheme

Verb ending used with he/she/it (she runs)

Copula (Main Verb "To Be")

A form of "to be" used as the main verb in a sentence (I am cold)

Auxiliary "To Be"

A helping verb used with another verb (She is running)

Overgeneralization

When a child applies a grammar rule where it does not belong (ex: goed instead of went)

Mazes

Repetitions or revisions in speech that are not counted in MLU calculations

SALT (Systematic Analysis of Language Transcripts)

Software used by speech-language pathologists to analyze language samples