Problem: What are the most important words?
wet revellers shelter form the rain at festival
Answer: festival, rain, shelter

Problem: What are the most important words?
A herd of zebra have surrounded a utility vehicle used for tours.
Answer: surround, vehicle, zebra

Problem: What are the most important words?
Several customers are observing a vendor weighing the produce they are buying.
Answer:
buy, observe, produce, vendor, weigh