When speaking English, it is important the students are not afraid to make a mistake. Sometimes, when I ask a student a question they hesitate for what seems like a long time. This could be for one of four reasons: didn't understand the question, didn't hear the question properly, didn't know how to reply or were just afraid to make a mistake. As long as they can give some sort of quick reply in English then they shouldn't be punished. Appropriate answers for the above examples would be: "I don't understand the question", "Say again please" and "I don't know how to answer