Instruct: Classify Amazon reviews into positive or negative sentiment
Query: A Must-Have!

This book is my constant companion while exploring the outdoors in the Rocky Mountains. Wonderful layout, great pictures, lots of detail so you're sure to get the correct ID... and great facts to add depth to your knowledge of the trees, shrubs, and flowers. I love this book, and highly recommend it to anyone living - or even visiting - the lovely Rocky Mountains.