Indicators of grammatical development based on a questionnaire for the assessment of early communicative skills

The aim of the study was to systematically assess the occurrence and age-related increase of functional words and specific grammatical parameters in the early language of Serbian children between 8 and 30 months of age based on the adapted version of MacArthur-Bates’ Communicative Development Inventories (CDIs). The sample included 126 mothers assessing their child’s language by means of the CDI-1 for ages 8-18 months, and CDI-2 for ages 16-30 months. The first questionnaire registers the occurrence of early grammatical words (pronouns, interrogatives, prepositions). The second is intended to evaluate the acquisition of the complex grammatical system: pronouns, prepositional constructions, noun morphology, modal and auxiliary verbs, conjugation, tense, negation, indicators of length and complexity of utterances. The results of the CDI-1 reveal the occurrence of early grammatical words at the age of 13 to 15 months: pronouns to 'this', moj/moja/moje ‘my’, and mene/me ‘me’, and the preposition o ‘on, about’. The first Wh-questions gde ‘where’ and kada ‘when’ appear at the same age. A larger variety of grammatical words in the sample was recorded at the age of 16 to 18 months: 9 pronouns out of 14 from the list are recorded, 11 prepositions (out of 12 from the list), as well as the first occurrence of the Wh-questions šta ’what’ and zašto ‘why’. Significant increase was recorded in CDI-2 for the following morpho-syntactic categories (five age groups in the range of 16-30 months, p<0.05): diminutive, possessive adjective, verb person, regular and irregular plural of nouns, preposition-case construction, negative verb forms, present and past tense, while the future tense is not mastered even at the older age levels. The longest utterance increases with age and reaches a length of 5.3 words at 25-27 months of age. The evidence of utterance complexity is recorded in the use of modal verbs, possessive pronouns, possessive adjectives, Wh-questions, dependent clause, direct v