Correction grammatical text book

120 page 17000 words science fiction  book, need Ingles language check grammatic spelled.
                              INTRODUCTION




This is a story that arises from an investigation developed through a premise, in which butterflies take a leading role, since they are the thread of connection with other dimensions. In this story two children with symptoms of autism are involved, although they also have extraordinary faculties to perceive the presence of beings outside planet Earth. They inherited this gift to safeguard the Six Keys that open the gates of knowledge. At their young age, they have to go through many unknown trials and face an evil reptile, who has in captivity the Warriors of Light, with the desire to seize the keys that open the universes and thus become the sole owner. The indisputable power of innocence and good over evil, once again, are triumphant before the millenary prophecy of the universes, in which the privilege that our human species has is emphasized, unlike other worlds: precisely, from what is narrated in this brilliant story, purity, innocence and free will stand out, that makes us unique to others content.