Kindersprache (Sprachverständnis) ; Children's comprehension of language; Language comprehension in children ; Learnability (of language) ; Lernbarkeit (von Sprache) ; Spracherwerb (Theorie) ; Language acquisition (theory of) ; Poverty of the stimulus-argument; Theory (language acquisition) ; Innate ideas hypothesis; Poverty of the stimulus-argument; Lernbarkeit (von Sprache) ; Learnability (of language) ; Nature/nurture; Logisches Problem (Spracherwerb) ; Logical problem (language acquisition) ; Nativist hypothesis ; Second language acquisition (psycholing.) ; Entrenchment (second language acquisition) ; Reinforcement (second language acquisition)