Task: Question Answering
Input (English): Context: As a Navy clinical psychologist assigned to a Marine operational unit , I was authorized to wear their uniform . The corporal rolled forward in his wheelchair and shook my hand firmly . " You have no idea how great it is to see that uniform , ma'am , " he said with a grin . 
Question: Why did the corporal grin ?
Output (English): He appreciated seeing the familiar uniform again .