Problem: What are the most important words?
wood grain and color tell a lot about the history of furniture .
Answer: furniture, lot, tell

Problem: What are the most important words?
shipment of the car into a cargo ship the sea port
Answer: car, port, shipment

Problem: What are the most important words?
Several suitcases piled on luggage carts at an airport.
Answer:
airport, cart, pile, suitcase