Problem: What are the most important words?
A train station with a train departing with passengers.
Answer: depart, passenger, station, train

Problem: What are the most important words?
fell walkers descending from the summit under a clear blue sky
Answer: fall, summit, walker

Problem: What are the most important words?
A piece of chocolate shaped like a Star Wars space ship and another piece of chocolate cake.
Answer:
cake, piece, shape