Why is graphite soft, and why is its melting point so high?
I think you might have to ask a question here.
Graphite is a non-molecular species, and consists of an infinite array of carbon atoms, covalently bonded in 2 dimensions. Perhaps, because it is a layered structure, graphite is soft. As a non-molecular species its melting point is impossibly high. Anyway, please refine your question.