Problem: What are the most important words?
time lapse footage with pan left motion of clouds over national park in the daytime at national park
Answer: daytime, footage, motion, pan

Problem: What are the most important words?
politicians listen to a speech by prime minister
Answer: minister, politician, speech

Problem: What are the most important words?
A lot of ships surrounding a pier on the water.
Answer:
ship, surround, water