Noun Phrase Accessibility Hierarchy (NPAH) as predictor of relative clause acquisition difficulty¶

Design · All designs
Evidence · 1 claim (1 for) · 1 study (1 causal), q3 · 0 of 1 report an effect size · 1 claim rests on one study

Description¶

The NPAH is a typological markedness hierarchy ordering relative clause types by accessibility of the relative pronoun's function. The article reports that "the implicational accessibility ordering continues as follows: DIRECT OBJECT, then INDIRECT OBJECT, then OBJECT OF A PREPOSITION, then POSSESSIVE, and finally OBJECT OF A COMPARISON", with SUBJECT relativization universally easiest. It was used to select the instructional sequence and to interpret acquisitional findings from FLA and SLA studies.

Design Implications¶

Context¶

Requirements¶

Descriptive and acquisitional research on the target grammatical subsystem to inform sequencing decisions

Constraints¶

The article notes exactly what constitutes difficulty has not yet been clearly established

Target Learners¶

Intermediate-level ESL learners

Learning Goals¶

Acquisition of English relativization

Claims¶

Markedness Role Instructed Il Development [+M]

Examples¶

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Key Sources¶

Catherine Doughty. (1991). Second Language Instruction Does Make a Difference: Evidence from an Empirical Study of SL Relativization. SSLA, 13, 431-469. https://doi.org/10.1017/S0272263100010287

Page metadata

Field	Value
`type`	`design`
`id`	`npah-accessibility-hierarchy-relativization`
`title`	`Noun Phrase Accessibility Hierarchy (NPAH) as predictor of relative clause acquisition difficulty`
`description`	`The NPAH is a typological markedness hierarchy ordering relative clause types by accessibility of the relative pronoun's function.`
`status`	`review`
`generated`	by `process:settle-candidates` on `2026-10-17`
`trust`	unverified — no one has confirmed this page's content
`sources`	1 — `catherine-doughty-1991`

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