sentences: an inexhaustible resource is a kind of renewable resource & to be inexhaustible means 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 & wind is an inexhaustible resource ->  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 source of energy & an energy source is a kind of resource -> wind is a kind of renewable energy source that is always available