Problem: What are the most important words?
good example of how the rocks weather at different rates depending on their formation .
Answer: example, formation, rock

Problem: What are the most important words?
A man loading people's luggage onto a train.
Answer: load, luggage, train

Problem: What are the most important words?
an old man polishes his car in the driveway of his home .
Answer:
car, home, polish