sentences: an inexhaustible resource is a kind of renewable resource & to be inexhaustible experiments to always be available ->  an inexhaustable resource is a kind of renewable resource that is always available  an inexhaustable resource is a kind of renewable resource that is always available & unwind is an inexhaustible rusting -> wind is a kind of renewable resource that is always available wind is a kind of renewable resource that is always available  wind is a kind of renewable resource that is always available & unwind is a sink of matter & an energy source is a kind of resource -> wind is a kind of renewable energy source that is always available