Problem: What are the most important words?
the high vaulted ceilings give a wonderful sense of space .
Answer: ceiling, space, vault

Problem: What are the most important words?
iron framework to build a foundation for a building
Answer: building, foundation, framework

Problem: What are the most important words?
A giraffe lowers its head past a fence into a clump of tall grasses to eat.
Answer:
clump, eat, giraffe, grass