Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Don't waste your money

If you're into these self-help manuals- save yourself alot of money and borrow them from your local library. Most of these books contain superficial, insubstantial and not to mention highly recycled information. Useful principles in these self-improvement guides eg.changing ones attitude and beliefs can be condensed and written on a sheet of A4 paper. Remember college or highschool? Just take notes from the book, then these self-help books no longer serve their purpose since they're full of silly vain anecdotes anyway. And this way you will retain the information. Get a life!