8.Watching TV has bad effects.Please figure out the reasons

we all know that watching TV is a way to kill time when we have nothing to do,but actually ,if we watch TV for a very long time,it could lead to the bad effects upon us,you can see ,one of the reasons is to harm your eyes for the continous looking at the TV,our eyes never move away from TV until our favorite program finish,to some extent,TV ad help us to have a rest for our eyes.another reason for the bad effects is bad for our health,you know ,we can't always be the couch-potato all the time,that would make us fat sitting on the couch like a still potato,that's not the healthy,we had better go out for a walk or do something besides watching TV.last but not the least,we would be lack of thinking about anything or our friends but the TV programm,sometimes ,watching TV could be a kind of waste of time.however,you can still have a lot of fun ,when you really know how to control yourself on watching TV