Complex sentence: His most known book, published in many languages, is "The Death of the Prophet", written in 1979 and offering a conclusion to the well known Khalil Gibran's books "The Prophet" and "The Garden of the Prophet".
Split into simpler sentences: His most known book is "The Death of the Prophet", written in 1979 and thereafter translated in many languages. It offers a conclusion to the well known Khalil Gibran's books "The Prophet" and "The Garden of the Prophet".