The acquisition of linguistic comprehension and expression skills is a cumulative process that begins with the birth of the baby. As soon as the baby is born, he begins to hear phonemes and to identify the verbal structures that he will gradually acquire in order to communicate with those around him and thus meet his needs.

In this article we will describe the stages of language development in young children , from the first undifferentiated vocalizations to the acquisition of the complex components of speech that in the long term will allow the improvement of communicative abilities.

The stages of language development

The main stages in the evolution of language are as follows

1. The preverbal or pre-linguistic period

Early in life, babies make sounds that are increasingly communicative and close to language. Maternal speech, characterised by a slower rhythm , frequent repetition, shorter sentences, grammatical simplification and clear pronunciation, can be helpful in the progressive development of the child’s linguistic understanding.

Pre-verbal interactions between the baby and other people are termed proto-conversations because they have a structure similar to dialogues. This language background is complemented by non-verbal responses such as hand gestures or facial expressions.

Among the pre-linguistic signs, the “protos” stand out. The protoimperials appear around nine months ; the baby points to an object to indicate to another person that he wants it. We speak of protodeclaratives, which develop at twelve months, when a similar gesture is intended to draw the attention of the adult to something.

In the first year of life, babies’ sounds progress from the first reflex vocalisations, such as grunts and cries, to cooing (consonants, vowels or simple combinations such as “gu”) and babbling, consisting of the production of syllable chains ; initially these are repeated, but later different syllables are combined.

The first words appear at approximately twelve months of age. At this time, babies tend to skip and replace phonemes, as well as bring two successive consonants closer together for ease of pronunciation; this is known as “assimilation”.

2. The Holophrasic Period

The term “holophrase” is used to speak of the one-word phrases , which are characteristic of the second stage of language development. During the holophrase period, words perform functions that will later correspond to sentences.

The meaning of holophrases depends to a great extent on the context in which they are pronounced and on the non-verbal language. Thus, if a baby says “baby” he is probably asking for a bottle, but if he points to it he may want to say “This is a bottle”, for example.

The holophrase will constitute the core of linguistic development: despite the lack of grammar in these constructions, its appearance indicates that the baby understands that the basic aim of verbalizations is to transmit a certain meaning to other people.

Babies usually reach the holophrasic period when they are about one year old. Later on their vocabulary will increase rapidly and intensely and they will gradually start to combine different words.

3. First word combinations

The holophrasic period ends shortly before the age of two. At this age the baby’s vocabulary has become very complex, so that he is already able to combine words and therefore meanings . This is the first time that subjects and predicate appear explicitly, although it is not yet clear that the little one distinguishes between categories of words.

Between the ages of two and three, children begin to combine three or more words on a regular basis, resulting in surprisingly rich sentences. They also learn to use different intonations that allow them to use the interrogative mode, for example.

The first combinations of words are known as “telegraphic speech” because the little ones avoid the less informative components of the sentences, such as determinants and conjunctions, giving priority to verbs and nouns; the latter constitute the bulk of the words learned during this stage of linguistic explosion.

4. Advanced language development

In the period between approximately 16 months and 4 years, children’s vocabulary increases exponentially. When they reach this age their linguistic ability begins to approximate that of adults progressively, although it will take several years for them to perfect both their vocabulary and grammar.

There is a dissociation between the understanding and the production of language. In particular, young children are capable of understanding complex sentences that they will not be able to generate on their own until more than two months later.

There are two very frequent types of errors during the time of language acquisition: overextensions and underextensions . The former are generalizations consisting of using one word to designate other objects, such as calling all mammals “dogs”; the under-extensions or sub-generalizations are errors opposed to these.

As children grow up, there are several milestones that will be critical to adult language development. Among others, the identification of irregular forms, the acquisition of verbal modes and the progress of metalinguistic and metacognitive knowledge are of great importance.