English as a second language; ESL; TESOL ; Frequency (pragm.) ; Discourse analysis (pragm.) ; Diskursgrammatik; Gesprächsanalyse; Konversationsgrammatik; Conversational analysis (pragm.) ; Discourse marker ; Comparison ; Second language acquisition (pragm.) ; Zweitspracherwerb (pragm.) ; Interactionist hypothesis (second language acquisition) ; Conversational analysis (second language acquisition) ; Lemmata ; English (American) ; USA (English language in the) ; USA (engl. Sprache in den) ; English in the USA; Englisch in den USA; American English