Aim/Purpose: To examine the use of a flipped classroom in the English Language subject in secondary classrooms in Hong Kong. Background: The research questions addressed were: (1) What are teachers' perceptions towards the flipped classroom pedagogy?; (2) How can teachers transfer their flipped classroom experiences to teaching other classes/subjects?; (3) What are students' perceptions towards the flipped classroom pedagogy?; (4) How can students transfer their flipped classroom experiences to studying other subjects?; and (5) Will students have significant gain in the knowledge of the lesson topic trialled in this study? Methodology: A total of 57 students from two Secondary 2 classes in a Band 3 secondary school together with two teachers teaching these two classes were involved in this study. Both quantitative and quantitative data analyses were conducted. Contribution: Regarding whether the flipped classroom pedagogy can help students gain significantly in their knowledge of a lesson topic, only one class of students gained statistically significantly in the subject knowledge but not for another class. Findings: Students in general were positive about the flipped classroom. On the other hand, although the teachers considered that the flipped classroom pedagogy was creative, they thought it may only be useful for teaching English grammar. Recommendations for Practitioners: Teachers thought that flipping a classroom may only be useful for more motivated students, and the extra workload of finding or making suitable pre-lesson online videos is the main concern for teachers. Recommendations for Researchers: Both quantitative and qualitative analyses should be conducted to investigate the effectiveness of a flipped classroom on students' language learning. Impact on Society: Teachers and students can transfer their flipped classroom experiences in English Language to teaching and studying other subjects. Future Research: More classes should be involved and a longer period of time should be spent on trial teaching in which a flipped classroom can be implemented in different lesson topics, not only teaching grammar. Teachers also need to determine if students can use the target language item in a task.