Problem: What are the most important words?
trees and clouds reflected in a calm river
Answer: cloud, reflect, river, tree

Problem: What are the most important words?
you can cool off from the hot sun by taking a dip in the sea at beach .
Answer: dip, sun, take

Problem: What are the most important words?
biological species perched on a tree getting soaked in the rain
Answer:
perch, rain, tree