The sign language is a means of guaranteeing two-way information accessibility. It is the most effective in discussion-type lessons. Students who are deaf or hard of hearing use the sign language as their mother tongue. They can understand it with a minimum of stress. There is a need for sign language interpreters capable of expressing prosodic factors visually through facial cues and so forth in order to enable deaf students to take part in “active lectures’ where students can participate with having understood the feelings of others.