You are provided with an "Event" and it's "Intent" related to PersonX. Determine the sentiment value of the given input as either "Positive", "Negative", and "Unknown". 

[EX Q]: Event:PersonX prevents ___ from obtaining. Intent:
[EX A]: Negative

[EX Q]: Event:PersonX kills PersonY on the spot. Intent: 1) something from my parents 2) my parents to allow something
[EX A]: Negative

[EX Q]: Event:PersonX keeps up appearances. Intent: 1) to reach his goal
[EX A]:
Negative