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: I'm going On The Record with Greta Van Susteren tonight at 6:00 CDT. Be sure to tune in!  Responser: Will do! Great speech last night.
