# Children's Understanding of Necessity Modals: Evidence from French

Oana Lungu, Anouk Dieuleveut, Valentine Hacquard, Ailis Cournane

► To cite this version:

Oana Lungu, Anouk Dieuleveut, Valentine Hacquard, Ailis Cournane. Children's Understanding of Necessity Modals: Evidence from French. Boston University Conference on Language Development, Nov 2025, Boston (MA), United States. hal-05515967

HAL Id: hal-05515967

https://hal.science/hal-05515967v1

Submitted on 17 Feb 2026

HAL is a multi-disciplinary open access
archive for the deposit and dissemination of sci-
entific research documents, whether they are pub-
lished or not. The documents may come from
teaching and research institutions in France or
abroad, or from public or private research centers.

L'archive ouverte pluridisciplinaire HAL, est
destinée au dépôt et à la diffusion de documents
scientifiques de niveau recherche, publiés ou non,
émanant des établissements d'enseignement et de
recherche français ou étrangers, des laboratoires
publics ou privés.

<figure><img src="image_1.png" /></figure>

Distributed under a Creative Commons CC BY 4.0 - Attribution - International License
Children's Understanding of Necessity Modals: Evidence from French

Previous research shows that English-speaking 4–5-year-olds struggle with necessity
modals (e.g., *have to*), over-accepting them in possibility contexts, despite their early mastery
of possibility modals (*can, might*) [2–3, 8–12]. What underlies these difficulties with necessity
modals? Are they due to the lower frequency of necessity modals in English child-directed
speech (28% necessity vs. 72% possibility [8])? We address this question by testing children in
French, a language in which modal frequency is flipped, with necessity modals (*falloir, devoir*)
more common than possibility modals (*pouvoir*) (62% vs. 38%), with *falloir* (53%) more
frequent than *devoir* (8%) [7]. If frequency of exposure drives learning, French children should
perform better, with *falloir* results similar to *pouvoir* and better than *devoir*. Instead, for both
necessity modals, we find that children show the same difficulties that were found for their
English-speaking peers, suggesting that these difficulties reflect problems with learning
necessity modals more generally, and are not driven by frequency.

**Methods.** 36 French children (range=3;9-5;9, mean=5;01) and 43 adults completed a TVJT [4], using goal-oriented modals. For children, the task was presented on computer with pre-recorded audio stimuli; adults participated online via PCIbex [13]. Materials adapted from [3] featured stories about Cora the cat, who visits shops to gather items for a party. Onscreen puppet Léo makes statements that participants evaluate as correct or incorrect. Each story involves two roads to a store. We varied CONTEXT: *Possibility* (both roads open), *Necessity* (one blocked, with the open road mentioned), *Impossibility* (blocked road mentioned) within-subjects, and MODAL (*pouvoir, devoir, falloir*) between-subjects (12 children per modal). Participants saw 15 test items (5 per context) and 4 training items. **Fig.1** illustrates sample stimuli and procedure. **Table 1** summarizes the conditions and expected responses by modal.

**Results.** A mixed-effects logistic regression model showed significant main effects of GROUP ($\chi^2(1) = 12.08, p < .001$), MODAL ($\chi^2(2) = 21.74, p < .001$), CONTEXT ($\chi^2(2) = 38.89, p < .001$), and a significant GROUP-by-MODAL interaction ($\chi^2(2) = 12.16, p = .002$), indicating that children differed significantly from adults in their responses to different modal verbs. Pairwise comparisons (Tukey-adjusted) showed that, in *possibility* contexts, children gave significantly more “yes” responses than adults to *devoir* and *falloir* (p < .01) but not to *pouvoir* (p = .9). While adults showed clear distinctions among the three modal verbs (*pouvoir* eliciting significantly more “yes” responses than *devoir* or *falloir*), children did not exhibit such differences in *possibility* contexts.

**Discussion.** French preschoolers over-accept necessity modals in possibility contexts, like their English-learning peers [3]. This suggests that input frequency alone does not explain their difficulties: *falloir* is common in French input, yet children still show difficulties with it. Children’s relative difficulty with necessity modals may rather be conceptual or semantic in nature: children may struggle to reason about necessity [10,12], or they may initially interpret necessity modals as expressing possibility [6]. These results are consistent with a learning bias toward possibility meanings ([3,8]) and challenge strongest meaning first accounts ([1,5] a.o).
<figure><img src="image_2.png" /></figure>

**A. Narrator:** Cora va au magasin de décorations pour acheter des décorations pour la fête.
*Cora is going to the decoration store to buy decorations for the party.*

**B. Narrator:** Il y a deux chemins pour aller au magasin de décoration : le chemin rouge et le chemin marron. [Animation - barrier drops] Mais zut, le chemin rouge est bloqué !
*There are two ways to get to the decoration store: the red road and the brown road.*
[Animation - barrier drops] *But uh oh! The red road is blocked!*

**C. Léo:** Pour aller au magasin de décoration, Cora _doit_ prendre le chemin marron.
*To get to the decoration store, Cora has to go down the brown road.*

**Prompt (Narrator):** Il a raison, Léo ? / Is Léo right?

<caption>Fig. 1. Stimuli and procedure for sample item (Modal: devoir, Context: Necessity)</caption>

<table><caption>Table 1. Expected responses by Condition (CONTEXTxMODAL)</caption><thead><tr><th></th><th>Possibility</th><th>Necessity</th><th>Impossibility</th></tr></thead><tbody><tr><td>Pour aller au magasin de décorations, Cora peut/doit/ il faut prendre le chemin marron.<br>(To get to the decoration store, Cora can/has to go down the brown road)</td><td></td><td></td><td></td></tr><tr><td>Pouvoir</td><td>Yes</td><td>Yes (on logical meaning)</td><td>No</td></tr><tr><td>Devoir, Falloir</td><td>No</td><td>Yes</td><td>No</td></tr></tbody></table>

<figure><img src="image_3.png" /><figcaption>Fig. 2. Percentage of yes responses (children and adults) by context faceted by modal</figcaption></figure>

**Selected references:** [1] Berwick (1985). *The acquisition of syntactic knowledge*. MIT Press. [2] Cournane. (2020). Learning modals. *LLC*; [3] Cournane, Dieuleveut, Repetti-Ludlow & Hacquard (2021). Testing modal force acquisition beyond the epistemic paradigm. *GALANA* 9; [4] Crain & McKee (1985). Acquisition of structural restrictions on anaphora. *NELS*; [5] Crain, Ni & Conway (1994). Learning, parsing and modularity. *Perspectives on language processing*; [6] Dieuleveut (2021). *Finding modal force* (Doctoral dissertation, U. Maryland); [7] Dieuleveut & Noveck (2023). Devoir, ou pouvoir, that is the question. *ELM3*; [8] Dieuleveut, van Dooren, Cournane, & Hacquard (2022). Finding the force. *NLS*; [9] Leahy & Zalnieriunas (2022). Might and might not. *SLT*; [10] Moscati, Zhan & Zhou (2017). Children's on-line processing of epistemic modals. *JCL*; [11] Noveck (2001). When children are more logical than adults. *Cognition*; [12] Ozturk & Papafragou (2015). The acquisition of epistemic modality. *LLD*; [13] Zehr & Schwarz (2018). PennController for Internet Based Experiments (*IBEX*).