Problem: What are the most important words?
A small cheesecake with one missing piece lies on a plate.
Answer: lie, piece, plate

Problem: What are the most important words?
people sheltering from wind and sun under umbrellas in a rocky hollow
Answer: shelter, sun, umbrella

Problem: What are the most important words?
model of the human head showing major blood vessels and muscles .
Answer:
head, model, muscle