Syntactic development; Morphological development; Morphologie (Spracherwerb) ; Syntax (Spracherwerb) ; Grammatical development ; Spracherwerb und neurologische Entwicklung; Language acquisition and neurological development; Sprache und Denken (Ontogenese) ; Language and thought (ontogenesis) ; Cognitive development; Language acquisition and cognitive development ; Kindersprache (Sprachverständnis) ; Children's comprehension of language; Language comprehension in children ; Word classes ; Complementizer; Satzkonjunktion; Subjunktion; Conjunction ; English