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: Nudge your co-workers, share our page with your friends and help us spread the word. Our old page has 2,400 'likes' - let's try and start off on our first day with at least 100!  Responser: Keep up the good work! Thank you!!
