Introduction

I was recently asked by a member of the Facebook group I co-founded with Dylan Vinales, Global Innovative Language teachers how grammar structures should be sequenced in a curriculum. The easy answer is: from easier to difficult, of course, prioritising high-frequency structures. But how do we establish which structures are more easily learnable than others?

A researcher by the name of Manfred Pienemann, attempted to answer this question with a landmark study Pienemann, M. (1984). “Psychological Constraints on the Teachability of Languages.” Studies in Second Language Acquisition, 6(2), 186-214. This study laid the groundwork for his later development of Processability Theory (1998), which further expanded on how learners acquire grammatical structures in a fixed sequence.

Manfred Pienemann’s Learnability Theory suggests that language acquisition follows a predictable sequence due to human working memory’s cognitive constraints.His Processability Theory (PT) builds on this by explaining how learners acquire grammatical structures step by step, as their cognitive processing abilities develop.

Key concepts of Learnability Theory

1. Developmental Stages: Language structures are acquired in a sequence, meaning some grammatical forms cannot be learned before others.
2. Teachability Hypothesis: Instruction can only be effective if it aligns with the learner’s current stage of acquisition. Trying to teach advanced structures too early is ineffective
3. Processing Hierarchy: Learners process simpler linguistic structures before tackling more complex ones.

Stages of French Language Acquisition Based on Processability Theory

Pienemann’s theory outlines a six-stage sequence for second language acquisition. Below is how this sequence applies to French learners:

Stage 1: Single Words and Fixed Phrases (No Real Grammar Processing)

At this pre-syntactic stage, learners rely on memorized words and formulaic phrases without grammatical manipulation.

• Bonjour ! (Hello!)
• Merci ! (Thank you!)
• Comment ça va ? (How’s it going?)
• Moi, Marie. (Me, Marie.)

Key Characteristics:

Learners do not yet process word order or inflections.
Responses are often formulaic and learned as whole chunks

Stage 2: Simple Word Order (Canonical Word Order – SVO)

At this stage, learners start forming simple Subject-Verb-Object (SVO) sentences.

• Je mange une pomme. (I eat an apple.)
• Il aime le chocolat. (He likes chocolate.)
• Marie regarde la télé. (Marie watches TV.)

Key Characteristics:

Learners can construct basic declarative sentences.
No agreement processing yet (gender, number).
No word order variation (such as inversion for questions).

Stage 3: Morphological Inflections (Lexical Morphology)

Learners begin processing grammatical markers like plural (-s), gender agreement, and verb inflections.

• Les pommes sont rouges. (The apples are red.) → (Plural agreement)
• Un petit garçon / Une petite fille (A small boy / A small girl) → (Gender agreement)
• Je finis mon travail. (I finish my work.) → (Present tense verb inflection)

Key Characteristics:

Learners begin applying regular inflections (e.g., plural -s, feminine -e).
Still inconsistent with irregular forms.
Errors in agreement (e.g., les grande maison instead of les grandes maisons).

Stage 4: Sentence Internal Reordering (Question Formation & Object Pronouns)

At this stage, learners acquire word order changes beyond the basic SVO structure. This includes:

1. Question Formation (Simple & Inversion)

• Tu as un chien ? (You have a dog?) → (Rising intonation, no inversion)
• Est-ce que tu as un chien ? (Do you have a dog?) → (Fixed structure)
• As-tu un chien ? (Have you a dog?) → (Inversion – more advanced)

2. Object Pronoun Placement

• Je vois Marie. (I see Marie.) → Basic SVO order
• Je la vois. (I see her.) → (Pronoun before verb – first instance of reordering)
• Je ne la vois pas. (I don’t see her.) → (More complex negative structure)

Key Characteristics:

Learners start reordering elements in sentences.
Questions evolve from declarative word order to inversion patterns.
Object pronouns begin appearing in correct positions.
Errors still common (e.g., Je vois la instead of Je la vois).

Stage 5: Subordinate Clauses & Complex Structures

Learners begin processing embedded clauses and subordinate structures.

• Je pense qu’il viendra demain. (I think that he will come tomorrow.) → (Subordination)
• Le livre que j’ai lu est intéressant. (The book that I read is interesting.) → (Relative clause)
• Si j’avais le temps, je voyagerais. (If I had time, I would travel.) → (Conditional sentences)

Key Characteristics:

 Learners can link ideas in longer sentences.

They produce relative clauses, conditionals, and reported speech.

Errors in conjugation and agreement still occur.

Stage 6: Full Processing of Advanced Structures

At this final stage, learners acquire full sentence reordering, advanced agreement, and complex clauses.

• Le professeur dont je t’ai parlé est ici. (The teacher whom I told you about is here.) → (Relative pronoun “dont”)
• Si j’avais su, je serais venu plus tôt. (If I had known, I would have come earlier.) → (Past conditional)
• Il faut que tu viennes demain. (You must come tomorrow.) → (Subjunctive mood usage)

Key Characteristics:

Learners master subjunctive, advanced conditionals, and complex reordering.
Proficiency level approaches native-like fluency.
Errors become minor and infrequent.

How Learnability Theory Guides French Teaching

1. Teach in the right order:
   • Start with simple sentences before introducing agreement rules.
   • Teach basic questions (Tu as un chien ?) before inversion (As-tu un chien ?).
   • Introduce object pronouns before relative clauses.
2. Respect processing constraints:
   • How many cognitive steps does the execution of a specific grammar structure involve? If working memory can only process about 4-6 items in younger learners and 5 to 9 in 16+ learners, will they cope with the cognitive load posed by the target structure?  

Example 1: the perfect tense with ETRE involves 6 or 7 mental operations/substeps. Are we sure that the target language learners can process all of them?

Example 2: A beginner won’t use the subjunctive correctly (Il faut que tu viennes) if they haven’t mastered basic verb conjugations first.

2. Trying to teach complex tenses (e.g., Si j’avais su, je serais venu) before learners are ready leads to confusion.
3. Provide appropriate input:
   • At early stages, focus on high-frequency structures (e.g., present tense, SVO order).
   • Gradually introduce complex grammar once learners can process simpler structures.

Conclusions

What does this mean for classroom practice at KS3 and KS4? First and foremost, that the order in which grammar structures appear in a textbook or GCSE specification should not dictate the order in which we teach them, since being able to explain a rule, complete a gap-fill exercise or reproduce a structure in a controlled task does not necessarily mean that learners are developmentally ready to deploy it spontaneously.

What the theory challenges is the assumption that explicit teaching, however effective, can simply override developmental constraints and guarantee spontaneous grammatical mastery. In other words, Processability Theory should inform our expectations of acquisition and our decisions about when to demand independent productive control, rather than be treated as a rigid prescription for curriculum sequencing.

Consequently, grammar instruction should be sequenced according to processing demands, not merely grammatical complexity or examination requirements, with high-frequency, readily processable constructions introduced first, extensively modelled through comprehensible input, practised in meaningful contexts and systematically recycled before more demanding structures are targeted for independent production.

Does this mean we should avoid exposing beginners to complex grammar altogether? Of course not! Learners can encounter and use sophisticated constructions as formulaic chunks long before they can analyse or manipulate their underlying grammar. The crucial distinction, therefore, is between exposure, controlled use and spontaneous productive mastery… a distinction which, if ignored, risks producing students who can perform grammatical operations on worksheets but struggle to deploy the same structures under the real-time processing pressures of GCSE speaking and writing.

Another potential risk concerns fossilisation, whereby non-target-like forms become deeply entrenched in a learner’s interlanguage and prove remarkably resistant to corrective feedback and further instruction. When students are repeatedly required to produce grammatical structures for which they lack the necessary processing resources, they may resort to simplification, avoidance or other compensatory strategies, potentially reinforcing inaccurate production. Does this mean that premature grammar instruction inevitably causes fossilisation? Not always. However, it does raise an important question: are we genuinely promoting grammatical development, or merely encouraging learners to rehearse forms they are not yet developmentally equipped to process accurately?

Table 1 – List of factors that increase the cognitive load of grammar structures