Interaction between the student and the instructor is important for the student to gain knowledge. Also, one of the major tasks on the instructor in e-learning is to reply student e-mails and posted messages. Students usually raise their questions by these two methods in an e-learning environment. In this paper, we introduce a semantic-based automated question answering system that can act like a virtual teacher to respond to student questions online. With the system, not only the instructor can be relieved from the load of answering lots of questions, but also the student can mostly get answers promptly without waiting for the instructor to get online and provide an answer. This would be a big help for both the instructor and the student in e-learning environment.

Through the process of raising questions and getting answers, the knowledge base will be enriched for future questions answering. Further, not only the students can get answersfor their questions, but also the instructors could know what problems students encounter in learning. These would be big aids to both the teaching and the learning.