Second language acquisition (language teaching) ; Zweitspracherwerb (Unterricht) ; Foreign language teaching ; Erstspracherwerb; First language acquisition; Ontogenese; Language acquisition ; Spracherwerb (lex.) ; Language acquisition (lex.) ; Vocabulary (language acquisition) ; Dual language acquisition; Bimodal language acquisition; Spracherwerb (biling.) ; Language acquisition (biling.) ; Bilingual language acquisition ; French