This paper reports the findings of a case study investigating the taxonomy of question-types in Hong Kong EFL classrooms, their appropriate application by teachers, and the resulting effectiveness in helping students understand the correct lesson objectives. Triangulation was conducted in data collection using classroom observations, teacher in-depth interviews, and student interviews. Results indicated low-cognitive questions were common. Of those, knowledge-based questions were most frequently used for teaching vocabulary or confirming student understanding. This was regardless of whether the lesson's nature was straightforward grammar or task-based learning. Other findings indicated that teachers used questions inefficiently to manage the classroom or stage lessons. High-cognitive questions, which engender practical English use, were rarely used. Teacher-selected question-types are evaluated for effectiveness, and implications for classroom pedagogy are discussed.