Definition: Given a 'poster' sentence and a corresponding 'response' (often, from Facebook or Reddit)classify the sentiment of the given response into four categories: 1) Positive, 2) Negative, 3) Neutral, and 4) Mixed if it contains both positive and negative.
Input: Poster: Who are you rooting for in men's and women's singles to win a Grand Slam at ROLAND-GARROS this weekend?  Responser: I was for Schiavone and will cheer Rafa on ~
