Watson was designed to answer Jeopardy questions. If Alex Trebek had used natural language to ask it anything other than a jeopardy question it would have failed spectacularly. ie, "So where are you from?".
It was tuned for that particular task, but the core tech is much more general - the current main application for which IBM is selling the Watson platform is healthcare, which is "a bit" different from answering Jeopardy questions.
Not really. "A runny nose, a fever, body aches" "What are symptoms of flu the with 75% accuracy?"
That's dumbed down of course. It's probably more like "This much of this enzyme concentration in blood, that thing in urine"
"What is a 17% chance of developing some condition in the next 5 years?"
It was definitely built for one specific task.