Can ghost hurt the living?

The bad ghost can have the ability to cause serious injury to a human being. The bad ghost can knock you on your own wall, or the ghost may turn your electrical appliances on and off, the ghost can even shake your bed. Ghosts have a bad reputation to the average person. Seeing a ghost is a terribly frightening experience. This is even true even when the person knows who the ghost is. Yet we will all be ghosts one day. Even if we don't stick around after our death we will die and become spirits. So there will be good ghost and there will be bad ghost but i think most of the ghost are good ghost. So yes, and no, ghost can and can't hurt the living. But people always question why do the ghost have to hurt other people is it just because when they were alive people hurted them. We just want to sent them free but they won't let us. It's like the ghost is being held back by something big and won't sent any of them free.  

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