Problem: What are the most important words?
politician addresses the audience and graduating cadets during the graduation ceremony .
Answer: cadet, ceremony, graduate, politician

Problem: What are the most important words?
a home in the hills is consumed from the inside out by flames yesterday
Answer: flame, hill, home

Problem: What are the most important words?
a shopper chooses a can of food filling at a supermarket
Answer:
fill, food, supermarket