Sometimes, I was suddenly in bad mood without special reason and didn't feel like doing anything, every that moment, I would rather sit alone than talk with somebody. I was not sure whether other guys had such similar condition, but I had some time. The bad mood may last for several hours, after hours, I can come back to normal, nobody can notice what was wrong during this moment. I always try to keep calm when I was in the bad mood, I didn't want to bring this negative attitude towards others, normally, I will feel better after I had a good rest. As to quality of sleeping, I felt I was in poor quality of sleep during the past years, remembered that I can sleep through the night when I was twenty years old, after good sleeping, I always feel full of energy, now I think the body organ begins to move backwards as the growth of age. From now on. I should do is to take care of myself and try to keep a positive attitude to life, no matter how rough I will face in the future, I should keep calm and believe that the methods are always more than difficulties.