English as a second language; ESL; TESOL ; Second language acquisition (psycholing.) ; Critical period (second language acquisition) ; Alter (Einfluss auf Zweitspracherwerb) ; Age (influence on second language acquisition) ; Ultimate attainment (second language acquisition) ; Near-native competence (second language acquisition) ; AoA; Age of acquisition (second language acquisition) ; Sensitive period (second language acquisition) ; Phonische Interferenz; Languages in contact (phon.) ; Sprachkontakt (phon.) ; Interference (phon.) ; English ; Italian