Problem: What are the most important words?
Parking meter at curb showing 3 hours and 55 minutes remaining.
Answer: hour, meter, minute

Problem: What are the most important words?
tube train arriving and coming to a stop at a station
Answer: arrive, stop, train

Problem: What are the most important words?
a fairy is a mythical creature of folklore and mystery dressed the colors of winter
Answer:
creature, fairy, folklore, mystery, winter