Problem: What are the most important words?
ants inspected dead lizard on the stone under light of hot sun
Answer: lizard, stone, sun

Problem: What are the most important words?
a student receives her diploma during the ceremony .
Answer: ceremony, diploma, receive, student

Problem: What are the most important words?
Apples and pears are in a box with grains and a bowl.
Answer:
apple, bowl, box