Problem: What are the most important words?
the ship passing by the fortified city as it enters parliamentary republic
Answer: pass, republic, ship

Problem: What are the most important words?
i need to get some mugs to have in my dorm room for hot tea and coffee
Answer: mug, need, tea

Problem: What are the most important words?
the author makes a friend on the way to the summit .
Answer:
author, summit, way