Florinda Jeni Mbitu Meja Pengarang Tans Feliks Dosen Pembimbing 1 Gupuh Rahayu Dosen Pembimbing 2 Tans Feliks Ketua Penguji Drs. Alexander H. Kabelen, MA Penguji 2 Gupuh Rahayu Penguji 1

Florinda Jeni Mbitu MejaThis study is entitled “An Analysis of Classroom Languages Used by An English Teacher and His Students in Teaching and Learning English at SMPN 20, KupangCity East Nusa Tenggara Province”. The aims of this research are to know the kinds of classroom languages used by the teacher and his students at SMPN 20,Kupang City East Nusa Tenggara Province and how the teacher and students use those classroom languages. The method use in this research was descriptive qualitative. The subjects of this research were the teacher and students at SMPN 20, Kupang East Nusa Tenggara Province. The data were collected through ofobservation. The subjects of this study were an English teacher and his students in grade eight. This study was done on January 26th, 2024 and February 5th, 2024. The writer found four classroom languages used by the teacher and his studentsin the classroom namely: Imperative sentences, interrogative sentences, positive sentences and negative sentences. The teacher and his students use those classroom languages formally and informally. Keywords: classroom language, teaching, learning English