a questionnaire about sleeping

1. How many hours do you sleep everyday in general? [填空题] *    

2. Do you agree that we should go to bed on time even if we do not feel really tired? [多选题] *    

3. Do you believe that sleeping is a natural instinct among all the animals? [多选题] *    

4. Do you know any plants which need sleeping? If you do,please list some.If not,just leave it blank [填空题] *    

5. Please list whatever you know about the reason caused the phenomenon of creature's sleeping [填空题] *