First, the most common thing in our life should be that after the teacher finishes a class, most students in the class actually understand it, and only a few students don't. If students ask questions to the teacher, the teacher can answer them. This is not an obligation, but a requirement of teachers' morality. As a teacher, when encountering knowledge points or questions that students don't understand, I help students to answer them enthusiastically and patiently. Even some teachers will explain the knowledge thoroughly as soon as they have time until the students learn it. This is what teachers need to turn their knowledge into students. A qualified teacher will do his best to treat students, regardless of their grades, which is also a sign of respecting a student. Teachers and students are both teachers and students, friends and respect each other.

Secondly, as far as I am concerned, since most students understand the teacher's lecture, it shows that the quality of the teacher's class itself is no problem, and individual students do not listen carefully, which leads to their inability to understand and learn. Generally speaking, if students can ask the teacher to answer questions on their own initiative, the teacher will not refuse. So do college teachers. For teachers, it is also a good opportunity for students to discuss knowledge by themselves. According to my understanding of universities, university teachers like to have students ask questions, which shows that this student is thoughtful, listens carefully in class to learn knowledge and has courage.

So it is not to answer students' questions, but a responsibility, morality and demeanor.