In theoretical linguistics, a speaker's judgement on the well-formedness of a linguistic utterance—called a grammaticality judgement—is based on whether the sentence is produced and interpreted in accordance with the rules and constraints of the relevant grammar. If the rules and constraints of the particular language are followed then the sentence is considered to be grammatical. In contrast, an ungrammatical sentence is one that violates the rules of the given language.

Linguists use grammaticality judgements to investigate the syntactic structure of sentences. Generative linguists are largely of the opinion that for native speakers of natural languages, grammaticality is a matter of linguistic intuition, and reflects the innate linguistic competence of speakers. Therefore, generative linguistics attempts to predict grammaticality judgements exhaustively. On the other hand, for linguists who stress the role of social learning, in contrast to innate knowledge of language, such as Hopper 1987 there has been a gradual abandonment of talk about grammaticality in favour of acceptability.[1]



The concept of grammaticality is closely tied to generative grammar, which has the goal of generating all and only the well-formed sentences in a given language.[2]

Criteria that determine grammaticalityEdit

According to Chomsky, a speaker's grammaticality judgement is based on two factors:

  1. A speaker's linguistic competence, which is the knowledge that they have of their language, allows them to easily judge whether a sentence is grammatical or ungrammatical based on intuitive introspection. For this reason, such judgements are sometimes called introspective grammaticality judgements.
  2. The context in which the sentence was uttered.

Criteria that don't determine grammaticalityEdit

In his study of grammaticality in the 1950s, Chomsky identified three criteria which cannot be used to determine whether or not a sentence is grammatical.[3]

  1. Whether or not the sentence is included in a corpus
  2. Whether or not the sentence is meaningful
  3. Whether or not the sentence is statistically probable

To illustrate this point, Chomsky created the nonsensical sentence in (1), which does not occur in any corpus, is not meaningful, and is not statistically probable. However, the form of this sentence is judged to be grammatical by many native speakers of English. Such grammaticality judgements reflect the fact that the structure of sentence (1) obeys the rules of English grammar. This can be seen by comparing sentence (1) with sentence (2). Both sentences have the same structure, and both are grammatically well-formed.

Tree structure of "Colourless green ideas sleep furiously"
(1) Colorless green  ideas   sleep furiously. (Chomsky 1957: 17)
(2) Harmless  young children sleep quietly.

A grammatical string is not necessarily meaningful, as exemplified by Chomsky’s famous sentence ‘Colorless green ideas sleep furiously’. However, language speakers can still understand nonsensical string by natural intonation and that speakers are able to recall them more easily than ungrammatical sentences. It is also suggested that speakers are supposed to have intuitions about grammaticality, which is determined by their competence on that language.[4]

Grammaticality versus acceptabilityEdit

Acceptability is the extent to which:

  1. a sentence is produced by the grammatical rules of that language;
  2. that sentence is considered permissible by speaker and hearer.

On the other hand, grammaticality is the extent to which a ‘string’ of language conforms with a set of given rules.[4]

It is assumed that a native speaker’s grammar generates grammatical strings and that the speaker also has the ability to judge whether this string is acceptable in that language. In practice, the two notions are frequently confounded and speakers are typically asked to give their ‘grammaticality judgements’ instead of ‘acceptability judgements’.[4] Lyons 1968 defines grammaticality as "that part of the acceptability of utterances which can be accounted for in terms of the rules", a criterion that complements acceptability for semantic soundness.[5] Grammaticality is defined by what a particular grammar can have as its output, while acceptability is speaker-oriented and depends upon what speakers will consider appropriate.[6]

Acceptability is gradientEdit

However, there are still modern linguists who side with the more traditional categorical interpretation of grammaticality, such as Sprouse (2007).[7] Speakers' judgements of the well-formedness of sentences form a continuous spectrum. While many grammaticality judgements are categorical, with a given sentence judged as either 'grammatical' or 'ungrammatical', there are many sentences that fall in a grey area of partial acceptability. According to Jon Sprouse (2007), the difference between grammaticality and acceptability is that grammatical knowledge is categorical, but acceptability is a gradient scale.[8]

The acceptability of a sentence is often reported in a variety of terms including acceptable, marginally acceptable, unacceptable, terrible, good etc. Degrees of acceptability are usually represented by symbols like *, ?,??, ?* etc., usually on a scale of 0-?-*-** (acceptable to unacceptable).

(3) *** The Sally hugged him the Thomas
(4) ** The Sally hugged him Thomas
(5) * The Sally hugged Thomas
(6) ??? Which the friend Thomas has painted a picture of?
(7) ?? Which friend Thomas had painted a picture of?
(8) ? Which friend has Thomas painted the picture of?

Note that examples (3)-(8) are open to interpretability as intuition of grammaticality is somewhat based on intuition so the degrees of grammaticality may range from individual to individual. Some linguists believe that the informal use of these diacritics is problematic because the exact meaning of the symbols have never been properly defined, and their usage is riddled with inconsistencies.[9][10][11]

Frequency affects acceptabilityEdit

Acceptability is about the performance of speakers, that is, the actual use of their language in concrete situations. As stressed by Chomsky, acceptability does not mean grammaticality: while an acceptable sentence must be grammatical, a grammatical sentence does not need to be acceptable. For a sentence to be judged acceptable, it must also appear natural and appropriate in a given context, be easily understood and, possibly, be to a certain extent conventionalised.[6]

The two need not match, below are two examples:

Tree structure of "Colourless green ideas sleep furiously"

Grammatical but not acceptable:

(9)  Colourless green ideas sleep furiously. (Chomsky 1957: 17)

Acceptable but not grammatical:

(10) But if this ever changing world in which we live in
     Makes you give in and cry
     Say live and let die. (Paul McCartney, 1973)

Example (9) is grammatical yet unacceptable since sleeping is not something that can pragmatically be described as being done furiously. Although the syntactic structure is grammatical, the semantic meaning does not make sense according to the English lexicon.

Example (10) is not grammatical because the same preposition (in) is both maintained in its original position and stranded. This contravenes the rules of English which allows either the entire prepositional phrase in which to be relativized, as in (11a), or the object of the preposition which to be relativized, as in (11b). However, (11c) is acceptable because of the frequency with which people hear it.[6]

(11) a.  This world [in which] we live [ __ ] ...
     b.  This world [which] we live in [ __ ] ...
     c. *This world [in which] we live in [ __ ] ...

That the relative acceptability of (11c) is related to a frequency affect is confirmed by the fact that ordinarily such sentences are judged to be ungrammatical, as shown in (12).

(12) a.  This table [on which] I put the book [ __ ] ...
     b.  This table [which] I put the book on [ __ ] ...
     c. *This table [on which] I put the book on [ __ ] ...

Other factors that determine acceptabilityEdit

The prevailing models on grammaticality since Chomsky (1965) postulate that the acceptability of sentences is a scale, with clearly acceptable on one side, clearly unacceptable on the other, and all manner of ranges of partial acceptability in between.[7] However, in spite of this linguists since Chomsky have tended to assume that grammaticality is categorical, or binary, and that a sentence either is or is not grammatical, with no partial grammaticality in between. To explain the scale of partial acceptability, these linguists have said that phenomena other than grammatical knowledge—such as plausibility, working memory limitations, etc.—account for speakers reporting acceptability on a scale. However, there are a few exceptions to this trend, including those who claim that "strength of violation" plays a role in grammaticality judgements. Examples of linguists of this persuasion include Huang's (1982) proposal that ECP violations are stronger than Subjacency violations, Chomsky's (1986) proposal that each barrier crossed leads to lower acceptability, and Optimality Theory (esp. Keller 2000, 2003).[7]

(13) Subjacency *[CP Whatj does [ TP Sue wonder [CP when I broke ___j]]]? (Sportiche 2014: 287)
(14) Barrier *Herselfj likes Maryj's mother

Subjacency says that you cannot relate two positions across two bounding nodes. In (13), we see that the movement of the wh-expression 'what' was moved past a CP and a TP to get to the Spec CP position- thus this phrase is ungrammatical.

Within the past twenty years however, there has been a major shift in linguists' understanding of intermediate levels of acceptability. This is due to the increasing use of experimental methods to measure acceptability, making it possible to detect subtle differences along a scale of acceptability. Keller (2000) and Fanselow et al. (2004) are two proponents of this new way to construe grammaticality.

Norm-based evaluationEdit

Prescriptive grammars of controlled natural languages define grammaticality as a matter of explicit consensus. On this view, to consider a string as grammatical, it should conform with a set of norms. These norms are usually based on conventional rules that form a part of a higher/literary register for a given language. For some languages, these norms are defined and periodically updated by an appointed body of experts whose rulings are occasionally questioned by the frustrated members of the public.[4]

Use of grammaticality judgmentsEdit

Investigating sentence processingEdit

There are several methods that successfully investigate sentence processing, some of which include eye tracking, self-paced listening and reading, or cross-modal priming. The most productive method however, is real-time grammaticality judgements. A grammaticality judgement is a test which involves showing participants sentences that are either grammatical or ungrammatical. The participant must decide whether or not they find the sentences to be grammatical as quickly as possible. Grammaticality is cross-linguistic, so this method has therefore be used on a wide variety languages[12] Grammaticality judgements are largely based on an individuals linguistic intuition, and it has been pointed out that humans have the ability to understand as well as produce an infinitely large number of new sentences that that have never seen before.[13] This allows us to accurately judge a sentence grammatical or ungrammatical, even if it a completely novel sentence.

Computer-assisted language instructionEdit

(Catt 1988) and (Catt and Hirst 1990) created a model of grammaticality based around a computer program developed for computer-assisted language instruction which was designed to perform automatic error diagnosis and correction of ungrammaticalities produced by second-language learners. The program classified errors made by language-learners in their sentences as being due to errors in phrase structure, transformations, morphology, verb subcategorization, or by the languages-learners translating their primary language directly into the language they are learning. The program worked primarily by utilizing a parser which consisted of constraints which, if a first parsing attempt failed, could be selectively relaxed. Thus, for a given parse, the constraints which were relaxed indicated the precise nature and location of ungrammaticality.[14]

Assessing first language (L1) competenceEdit

There have been experiments conducted in order to test how early speakers gain the ability to judge grammaticality in their native language. In an experiment by Cairns et al., preschool children aged 4–6 were presented sentences such as (15) and (16) orally. (To make sure that the meaning of the sentences was clear to the children, sentences were enacted with toys.) While sentence (15) is well-formed in the adult grammar, sentence (16) is not, as indicated by the asterisk (*). The source of the ill-formedness is that the verb hug is a transitive verb and so must have a direct object, namely something or someone who receives the action of the verb. Sentence (16) is missing the receiver of hug.

(15)  The kitten hugged the pig. [Carin 2006: 215]
(16) *The zebra hugged. [Carin 2006: 215]

The results of this study show that the earliest age at which children can discriminate well-formed from ill-formed sentences, as well as correct these, is at 6 years.[15] During the critical period between 4 and 6 years old, there is a significant increase in the accuracy of grammaticality judgments, since metalinguistic skill is in critical development; the judgment relies on the psycholinguistic ability of the child to access their internalized grammar and to compute whether it can or cannot generate the target sentence.[15] This ability to judge the grammaticality of sentences seems to develop in children well after basic grammar skills have been established, and is related to early reading acquisition—acquisitionists generally believe that the ability to make grammaticality judgments is a measure of syntactic awareness.[15]

Assessing second language (L2) competenceEdit

Late learners of L2 perform worse on grammaticality judgment tasks or tests than native speakers or early acquirers, in that L2 learners are more likely to accept a sentence that is ungrammatical as grammatical. After the critical period, age of acquisition is no longer supposed to have an effect, and native-like performance is no longer supposed to be achievable. However, the idea that there is a critical period for the acquisition of syntactic competence, which is reflected by the ability to assess the well-formedness of a sentence, is controversial. On one view, biological or language-specific mechanisms become non-functional after a certain age. On another view, decreased L2 learning ability with age is not inevitable, and can be explained by factors such as motivation, learning environment, pressure, and time commitment. Although there is evidence that supports the claim that speakers outside the L2 mastery age range are not capable of acquiring native-like mastery of a language, there is also evidence supporting the opposite, as well as evidence for young learners not mastering an L2.[16]

Performance-related factorsEdit

General processing problems, rather than a deficit in some syntax specific process or module, offer a viable explanation for populations that exhibit poor grammatical performance. Performance on L2 grammaticality judgments might be partially due to variable accessibility to and use of relevant grammatical knowledge. Difficulties in basic level cognitive processing is due to:

  • low L2 memory capacity
  • poor L2 decoding ability
  • slow L2 processing speed

These issues have been tied to grammatical processing performance by testing native speakers of English on the same tasks under stressful conditions: there is shown to be difficulty in grammatical agreement when memory capacity is curtailed, important cues in the language when given noisy input, and processing important structures when not given enough time to process input. This shows that knowledge cannot always be automatically and consistently applied under stressful situations without having processing difficulties. However, these issues are not necessarily independent of each other, as low decoding ability of structure could affect processing speed. Overall, individual differences in L2 working memory and decoding ability are correlated to grammaticality judgment accuracy and latencies. However, there is no correlation between speed of processing measure and grammaticality judgment performance, age of arrival correlates with syntactic mastery, and knowledge of vocabulary probably drives grammaticality performance.[17]

Age-related factorsEdit

Age for decrease of L2 grammaticality performance varies from early childhood to late adolescence, depending on the combinations of the speaker’s first and second language. The age of acquisition at which L2 learners are worse than native speakers depends on how dissimilar the L1 and L2 are on phonological and grammatical level. For example, Chinese/English bilinguals at 7 years old perform just as well as Spanish/English bilinguals at 16 years old.[18][19] This is due to the fact that a grammatical construction on an L2 that has a parallel structure in an L1 would impose less processing demand than one that does not have a parallel, causing a poorer performance on language structure.

There is evidence for late L2 learners generally having issues with plurals and past tense, and not so many issues with Subject-Verb-Object testing, in which they show native-like results; there is better performance on Yes/No as well as Wh- questions than on articles and past tense.[17]

There is data supporting high-performing late learners well beyond the critical period: in an experiment testing grammaticality by J. L. McDonald, 7/50 L2 English late-learner subjects had scores within range of native speakers.[17] The results are linked to how individual differences in L2 memory capacity, decoding, or processing speed affect processing resources to automatically apply the relevant grammatical knowledge.

See alsoEdit


  1. ^ Hopper, Paul (1987): Emergent grammar. In: Aske, Jon et al. (ed.) (1987): General session and parasession on grammar and cognition. Proceedings of the thirteenth annual meeting. Berkeley: BLS: 139–155.
  2. ^ Millar, Jim (2011). A critical introduction to syntax. New York: Continuum International Publishing Group. p. 119. ISBN 978-0-8264-9703-1. 
  3. ^ Chomsky, (1957): "Syntactic Structures", The Hague/Paris:Mouton
  4. ^ a b c d Chapman, Siobhan, and Routledge, Christopher, "Key Ideas in Linguistics and the Philosophy of Language", 2009
  5. ^ Lyons, John (1968): Introduction to Theoretical Linguistics. London: Cambridge University Press, ISBN 9780521095105 .
  6. ^ a b c Bauer, "Grammaticality, acceptibility, possible words and large corpora", 2014
  7. ^ a b c Sprouse, "Continuous Acceptability, Categorical Grammaticality, and Experimental Syntax", 2007
  8. ^ Sprouse, J (2007). "Continuous acceptability, categorical grammaticality, and experimental syntax". Biolinguistics. 1: 123–134. 
  9. ^ Bader, M.; Haussler, J. (2010). "Toward a model of grammaticality judgments". Journal of Linguistics. 46 (2): 273–330. doi:10.1017/s0022226709990260. 
  10. ^ Ross, John Robert (1979). Fillmore, Charles; Kempler, Daniel; Wang, William, eds. "Where's English?" (PDF). Individual differences in language ability and language behavior. New York: Academic Press: 127–163. 
  11. ^ Laporte, Eric (2015). "The Science of Linguistics". Inference. International Review of Science. 1 (2). 
  12. ^ Kail, M.; Lemaire, P.; Lecacheur, M. (2012). "Online grammaticality judgments in french young and older adults". Experimental Aging Research. 38 (2): 186–207. doi:10.1080/0361073x.2012.660031. 
  13. ^ Nagata, H (1988). "The relativity of linguistic intuition: The effect of repetition on grammaticality judgments". Journal of Psycholinguistic Research. 17 (1): 1–17. doi:10.1007/bf01067178. 
  14. ^ CARSON T. SCHUTZE, The Empirical Base of Linguistics, 1996
  15. ^ a b c Cairns; et al. (2006). "Development of a Metalinguistic Skill: Judging the Grammaticality of Sentences". Communication Disorders Quarterly: 213. 
  16. ^ McDonald, Janet L. (2000). "Grammaticality judgments in a second language: Influences of age of acquisition and native language" (PDF). Applied Psycholinguistics. 21: 395–423. doi:10.1017/s0142716400003064. 
  17. ^ a b c McDonald, Janet L. (2006). "Beyond the critical period: Processing-based explanations for poor grammaticality judgment performance by late second language learners.". Journal of Memory and Language. 55: 381–401. doi:10.1016/j.jml.2006.06.006. 
  18. ^ Johnson, J. S.; Newport, E. L. (1989). "Critical period effects in second language learning: The influence of maturational state on the acquisition of English as a second language.". Cognitive Psychology. 21: 60–99. doi:10.1016/0010-0285(89)90003-0. PMID 2920538. 
  19. ^ Birdsong, D.; Molis, M. (2001). "On the evidence for maturational constraints in second-language acquisition.". Journal of Memory and Language. 44: 235–249. doi:10.1006/jmla.2000.2750. 
  • Fetzer, A. (2004). Recontextualizing context: Grammaticality meets appropriateness. Philadelphia; Amsterdam: John Benjamins Pub.
  • Schutze, C. T. (1996). The empirical base of linguistics: Grammaticality judgments and linguistic methodology. University of Chicago Press.
  • Hopper, Paul (1987): Emergent grammar. In: Aske, Jon et al. (ed.) (1987): General session and parasession on grammar and cognition. Proceedings of the thirteenth annual meeting. Berkeley: BLS: 139–155.
  • Lyons, John (1968): Introduction to Theoretical Linguistics. London: Cambridge University Press, ISBN 9780521095105 .
  • Chomsky, (1957): "Syntactic Structures", The Hague/Paris:Mouton
  • Champman, Siobhan, and Routledge, Christoper. (2009). Key ideas in Linguistics and the Philosophy of Language. Edinburgh, GBR: Edinburgh University Press.
  • Cairns, H.; Schlisselberg, G.; Waltzman, D.; McDaniel, D. (2006). "Development of a metalinguistic skill: judging the grammaticality of sentences". Communication Disorders Quarterly. 27 (4): 213–220. doi:10.1177/15257401060270040401. 
  • Sprouse, J (2007). "Continuous acceptability, categorical grammaticality, and experimental syntax". Biolinguistics. 1: 123–134. 
  • Kail, M.; Lemaire, P.; Lecacheur, M. (2012). "Online grammaticality judgments in french young and older adults". Experimental Aging Research. 38 (2): 186–207. doi:10.1080/0361073x.2012.660031. 
  • Bader, M.; Haussler, J. (2010). "Toward a model of grammaticality judgments. Journal of Linguistics, 46(2), 273-330*Nagata, H. (1988). The relativity of linguistic intuition: The effect of repetition on grammaticality judgments". Journal of Psycholinguistic Research. 17 (1): 1–17. 
  • Sportiche. D., Koopman. H., Stabler. E. (2014) An introduction to Syntactic Analysis and Theory. Wiley Balckwell.