Middle school students have far too much homework. They usually have to sit up three or four hours every night doing their homework. Now one school in my hometown has made a rule of limiting homework. The homework is limited to an hour a day and the students have no homework on the weekend. I think this is an excellent idea that will allow students to live better and healthier lives. Less homework will give students more time to enjoy other pastimes .I have many books which I received as gifts from my parents and friends. They have been kept there on my shelf for several years! Because of homework, I will have not read a single one of them. With less homework, students will be freer to develop their interests in art, music and other hobbies. More time free from homework will get our physical health better. Many students like sports, but they have little time to play football, basketball, volleyball and so on. They hardly have time to have a trip or take part in any social activities. They must spend so much time solving math problems and doing grammar exercises. Besides, staying up late to finish their homework leaves many students exhausted in the morning. Not getting enough sleep is not only unpleasant; it also makes students more likely to get colds and other illnesses. The author of the passage may be   _  .
a teacher a student a parent a doctor