Contrary to most animals, humans communicate cooperatively. Infants (i.e. 10 to 12 months) begin in cooperative communication through the pointing gesture. This form of communication relies on their social-cognitive ability to direct the attention of others and to understand the attention-directing intentions of others.

Skills of intention-reading refer to social-cognitive abilities which are necessary to understand one’s intentions and which are foundational to all forms of human communication. Cognitive skills of pattern-finding refer to general cognitive processes of categorization, analogy, schema formation and distributional learning aimed at reconstructing the linguistic abstractions of a speech community to become productive and creative with the conventions of a language.

One theory of language acquisition is that children have innate knowledge of language (e.g. Chomsky) and these innate grammar structures constrain language development. Constructivist theories state that children acquire competence with a language mainly through cultural learning and other cognitive processes (e.g. categorization; analogy). In constructivist theories, children are biologically prepared for language but only in general ways (e.g. capacities for cultural learning).  

An utterance refers to the smallest unit in which a person expresses a complete communicative intention (e.g. ‘give’). It is used to direct a recipient’s attention to something and to express a communicative motive (e.g. through an emotional expression). A child needs to understand the communicative intention of an utterance before the child can use it. Adults help this by stressing the word in a sentence. When a child does not understand the sub-functions of an utterance, the child will not be able to use it in different situations (e.g. novel situations).

Children learn words by attempting to understand utterances. To understand utterances, children often need to determine the functional role of a word. To learn a new word, children must extract it from a larger utterance and connect it to the relevant aspect of the current situation. Children learn the function of an utterance or word and this is how they begin to learn language.

A linguistic construction refers to a unit of language that comprises multiple linguistic elements used together for a relatively coherent communicative function. The elements also perform sub-functions. Constructions vary in their complexity depending on the number of elements and interrelations and they also vary in their abstractness. This makes that people know the general profile of an event in a sentence without knowing anything about individual content words (i.e. grammatical structure tells us who does what).

Holophrases refer to one-unit utterances with an intonational contour expressing communicative motive. Children begin speaking language by using holophrases. The initial schemas and constructions of children are very concrete and are organized around particular words and phrases instead of around abstract categories. The utterance-level constructions underlying children’s earliest multi-word utterances have three types:

1. Word combinations (18 months)
   This refers to a combination of two words or holophrases in situations in which they both are relevant, with both words having equivalent status (e.g. ball table). It partitions the experience of a child in multiple symbolic units.
2. Pivot schemas (18 months)
   This refers to utterances that are structured by a single word or phrase. This means that one utterance/word is used with a wide variety of object labels (e.g. more milk; more grapes; more juice). These schemes are organized around particular words with only one slot that is abstract and do not have syntax.
3. Item-based constructions (i.e. verb-island constructions)
   This refers to a construction which has a syntactic marking as an integral part of the construction although the syntactic marking is verb-specific (i.e. it depends on how a child has heard a particular verb being used). This means that children’s early grammatical productions are item-specific.

Children tend to use words and utterances in already established pivot schemes (e.g. repeat the verb in a way that is known rather than use it in a new way). Children tend to move away from verb-island constructions around their third birthday. The process of constructing more abstract constructions begins between two and three ears of age. However, they all have a particular communicative function:

1. Identificationals, attributives, and possesives.
   This serves to identify an object or to attribute to it some property (e.g. that’s a; that’s; this is my).
2. Simple transitives and intransitives
   This serves to indicate or request an activity or state of affairs (e.g. Daddy cut the grass).
3. Datives, ditransitives, and benefactives
   This serves to indicate or request the transfer of objects between people (e.g. ‘he gave it to mommy”).
4. Locatives, resultatives and causatives
   This serves to indicate or request spatial or causal relationships (e.g. Put it on the table).
5. Passives and reflexives
   This serves to indicate things happening to people or things who are not active agents (e.g. He got hit by a car).
6. Imperatives and questions
   This serves to request actions without a subject (e.g. Don’t do that).

Children typically develop from using relatively fixed syntactic constructions in different situations to using more abstract constructions. Young children do not seem to have an overall rule for forming questions but have a collection of more item-based schemas that will become a set of more coherent and abstract constructions later in development.

According to usage-based theories of language acquisition, children acquire language using their general cognitive and social-cognitive abilities. This requires intention-reading skills for determining the meaning and communicative function of concrete pieces of language and pattern-finding skills to detect and construct abstract grammatical patterns of these meaningful uses of language.

Schematization refers to learning the recurrent concrete pieces of language for concrete functions and forming a relatively abstract slot designating a relatively abstract function. This schematization leads to item-based constructions. The formation of slots relative to constant items are affected by token and type frequency.

Token frequency refers to the frequency with which a specific form is heard in a sample. This predicts the selection of a constant item in a schema because a word that occurs more often can be picked more easily as a constant. Type frequency refers to the frequency with which different items of the same type (e.g. nouns referring to sought things) are heard. This predicts where slots are formed in relation to constant items.

To move from item-based constructions to abstract constructions, children need to form schemas that have no concrete items in common. The learning process that achieves this is an analogy; a form of schematization that places heavy emphasis on commonalities in relational structure. Analogies will be formed more easily if certain items always tend to fill certain roles (e.g. actor role is always filled by similar objects). The key skill in analogy formation is the ability to focus on detecting similarities in relational structure and this is central to the acquisition of grammar.

To cluster words and morphemes into categories (e.g. noun; pronoun), children must draw upon information about the world’s distribution and its function. Distribution refers to the types of neighbourhoods a words tend to inhabit. Functionally based distributional analysis refers to the identification of items in a category on the grounds that they occur in the same formal contexts and perform the same communicative function within an utterance.

Children may learn about different verb classes (e.g. manner of locomotion and motion in a specified direction) (i.e. entrenchment). It is likely that children only learn verbs for the constructions in which they have heard them. This is likely in early development but not in later development. The more often children hear a verb used in a particular construction, the less likely they will be to extend that verb to any novel construction (i.e. pre-emption). When children hear a verb used in a linguistic construction that serves the same communicative function as some possible generalization, they may infer that the generalization is not conventional (i.e. knowledge of semantic sub-classes of verbs). Entrenchment (1), pre-emption (2) and knowledge of semantic sub-classes of verbs (3) are constraining processes in learning language.

Entrenchment appears to work from 3-years-old. Pre-emption and semantic sub-classes begin to work later. Verb-argument constructions are constrained gradually as they gradually become more abstract.