Problem: What are the most important words?
an astronaut drifting in space is rescued by a space shuttle orbiting earth
Answer: astronaut, drift, orbit, rescue, space

Problem: What are the most important words?
brown and white husky bulls with short horns grazing in a pasture and having tagged ears
Answer: bull, graze, horn

Problem: What are the most important words?
A man plays on an instrument that does not look like the flute but sounds like one.
Answer:
instrument, look, sound