Synthesized answer
The provided passage describes the book "Words and Rules" by Steven Pinker and Arthur Morey, and outlines some of the profound mysteries of language that the book explores [Passage 1]. These mysteries include how language works and how humans learn to speak [Passage 1]. Additionally, the book investigates why languages change over time and why they possess numerous quirks and irregularities [Passage 1].
However, the passages do not explicitly list the specific questions that remain unanswered at the conclusion of the book. They only state the broad topics and profound mysteries that are explored within its pages [Passage 1].
Synthesized from the book passages below. Chat with the book on Feynman for follow-up.
From the book
Title: Words and rules by Steven Pinker, Arthur Morey Description: How does language work, and how do we learn to speak? Why do languages change over time, and why do they have so many quirks and irregularities? In this book, the profound mysteries of language are explored.