Task: Question Answering
Input (English): Context: Apparently he 's home from the rehabilitation center and grumping around the house with his usual vigor . Did you know that ? I did n't . I stopped on the way home to visit Grandma and he came out from the kitchen . That 's how I found out . Everyone seemed in good spirits . 
Question: Why was he grumping around the house with his usual vigor ?
Output (English): he recovered fast and well from since his time in the rehabilitation center.