Sleep

Today I slept a lot. I spent almost half of the day sleeping. Really have a good rest. But now I'm tired again. Going to sleep again. Research shown that people spend 1/3 of their life sleeping. If you can live up till 90 years old, we will be spending 30 years sleeping. What if this 30 years is put into other purpose rather than sleeping? Maybe you can't live up till 90 if you don't sleep. But I believe that there is a purpose for us to be sleeping. So let's sleep! zzz...