In a college classroom the lecturer took attendance for that hour. He checked the number of students present as per attendance and counted the number of students present in the class. The attendance showed 40 and as per heads it was 34 only. The lecturer became irritated. He advised the students ," You are coming to the college not only to learn the languages and subjects. You must be sincere and well disciplined. Don't give proxy for your friends. If you are present say '' present "; If you are absent say " absent ". "