TASK DEFINITION: In this task you are given a tweet. You must judge whether the author of the tweet is sad or not. Label the instances as "Sad" or "Not sad" based on your judgment. You can get help from hashtags and emojis, but you should not judge only based on them, and should pay attention to tweet's text as well.
PROBLEM: @SFBART This driver is telling the passengers we did a very good job and saved a life today. That's it. #tears

SOLUTION: Not sad

PROBLEM: Only God knows why things happen, sometimes it's just hard to understand. #sad #prayingforyou

SOLUTION: Sad

PROBLEM: God just replaced my sadness with laughter, can't go the whole day sad ...

SOLUTION:
Not sad