Syntax—the rule system that governs how words combine into sentences—is one of the most academically consequential language domains. Children who struggle with syntax often have difficulty not just in conversational speech but across reading comprehension, written expression, and classroom participation. For school-based SLPs, syntax therapy addresses some of the most complex and persistent aspects of Developmental Language Disorder and related conditions. This guide covers what syntax includes, developmental expectations for school-age children, and practical treatment approaches that work in school settings.
What Syntax Includes
The term "syntax" encompasses two closely related but distinct linguistic systems:
Morphology is the system of word-level grammatical markers—the small units that signal tense, number, possession, and agreement. English morphological markers include: present progressive (-ing), regular plurals (-s/-es), possessives (-'s), articles (a/the), regular past tense (-ed), irregular past tense, third-person singular present (-s), copula "be" (is/are/was), auxiliary "be," and regular and irregular comparatives.
Syntax proper refers to sentence structure—how clauses are organized and combined. Key syntactic structures that develop through the school years include: simple active sentences, negatives, questions (yes/no, WH-, tag), passives, relative clauses, coordinate sentences (and/but/so), and various types of subordinate clauses (causal, conditional, temporal, relative).
Both morphology and syntax are assessed and treated, though they require different techniques. Morphological errors are often easier to target in drills; complex syntax is better addressed through discourse-level activities.
Developmental Norms for School-Age Syntax
By school entry (age 5–6), most children have mastered basic sentence structure and most grammatical morphemes (though regular past tense and some irregular forms may still be emerging). The school years are characterized by continued growth in:
- Complex sentence types: Relative clauses ("The book that I read was long"), subordinate clauses ("She left because she was tired"), and passives ("The ball was kicked by the boy") emerge and are refined through ages 7–11.
- Morphological complexity: Irregular past tense, third-person singular, and comparative/superlative forms are solidified in the early school years. Derivational morphology (converting nouns to verbs, adjectives to nouns) continues developing through middle school.
- Mean Length of Utterance and T-unit length: Average T-unit length (independent clause + subordinate clauses) increases from approximately 7 words at age 6 to 11+ words by age 12.
- Clausal density: The number of clauses per T-unit increases with age, reflecting increasingly complex and embedded sentence structure.
Targeting Grammatical Morphemes
Grammatical morpheme targets are often the entry point for syntax therapy in younger school-age children and those with DLD. Brown's (1973) order of acquisition provides a sequence: present progressive, prepositions (in, on), regular plurals, irregular past tense, possessives, articles, regular past tense, regular third-person singular, irregular third-person singular, copula, and auxiliary "be."
Effective techniques for morpheme therapy:
- Focused stimulation: Provide high-density exposure to the target morpheme in meaningful contexts without requiring production. For past tense, narrate action pictures or short videos using past tense throughout the session: "He walked to the store. She jumped over the puddle. The dog barked."
- Recasting: When the child omits a target morpheme, immediately recast with the correct form: Child: "He walk to school." SLP: "Yes, he walked to school." Do not correct explicitly—recasting provides the correct model without interrupting communicative flow.
- Minimal pair activities: For morphemes that carry meaning distinctions (present vs. past tense, singular vs. plural), use picture pairs where the correct morpheme determines which picture is selected: "Show me: the boys jump" versus "Show me: the boys jumped."
- Elicited imitation: Ask the student to repeat target sentences. Elicited imitation is a sensitive measure of syntactic knowledge and also a teaching technique—students reliably simplify sentences they can't fully process, revealing which structures are not yet internalized.
Targeting Complex Sentence Types
Complex sentences—those with multiple clauses—are essential for academic language and narrative development. Students with DLD often use simple sentences even when complex structures would convey their intended meaning more precisely.
Relative clauses ("The girl who won the race smiled") are particularly important because they appear frequently in academic texts and are required for precise reference. Begin with subject relative clauses ("The man who runs the store") before object relative clauses ("The man that she called"), which are significantly harder.
Subordinate clauses include causal ("He cried because he fell"), temporal ("After she ate, she played"), and conditional ("If it rains, we'll stay inside"). Causal subordination is typically mastered first. Use story-based contexts and graphic organizers showing the causal relationship before requiring oral production.
Passive sentences ("The window was broken by the ball") are late-developing and are particularly challenging for students with DLD. They also appear frequently in academic texts. Address passives explicitly—many students with language impairment misinterpret passives as active sentences, reversing the agent and patient roles.
Sentence Combining
Sentence combining is an evidence-based technique in which students are given two or more short sentences and asked to combine them into a single, more complex sentence. Research from written language instruction shows that sentence combining improves both syntactic complexity and writing quality. It translates directly to oral language therapy:
"The dog barked. The dog was big." → "The big dog barked." or "The dog that barked was big."
"She ran fast. She missed the bus." → "Even though she ran fast, she missed the bus." or "She ran fast but still missed the bus."
Sentence combining provides multiple ways to express the same idea, which builds syntactic flexibility. Students who can combine in multiple ways are more likely to select complex structures in independent speech and writing.
Story Grammar Approach
Narratives provide an ideal context for targeting complex syntax because stories require relative clauses, subordinate clauses, and varied sentence types to express character motivations, causal sequences, and temporal relationships. Story grammar intervention—explicitly teaching the structural components of stories (setting, initiating event, internal response, attempt, consequence, resolution)—produces improvements in both narrative structure and syntactic complexity.
Use a story grammar map (visual template with labeled story components) as a scaffold, then ask the student to retell or generate stories while targeting specific syntactic structures. "Tell me why the character felt that way"—targeting causal subordination. "Tell me what happened after she found the key"—targeting temporal subordination.
Progress Monitoring for Syntax
Syntax goals require careful operationalization for progress monitoring. Vague goals like "uses complex sentences" are unmeasurable. Well-written syntax goals specify the target structure, context, measurement procedure, and criterion:
Example: "When retelling a 5-picture story sequence, [Student] will produce sentences with causal subordinate clauses ('because,' 'so,' 'since') on 4 out of 5 target opportunities across 3 consecutive data points."
Language sample analysis is the most sensitive progress measure for syntax. Collect a 50-utterance sample monthly, calculate T-unit length and clausal density, and track specific target structures across time. Software tools can automate much of this analysis and flag trends in the data.