Instruct: Classify a review into positive or negative sentiment.
Query: It does not work, it makes your vision even poorer

I started doing the exercises on the 14th October 2010, from -3.0 it got worse to -4.0 in 2 months! I blame the stupid light therapy for it, I was warming my eyes with a light bulb and here I am with a stronger prescription.Terrible experience, the authors are cheating us all.