What are the keywords in the following sentence? A train traveling past a row of four smoke stacks.
stack, train, travel

What are the keywords in the following sentence? cars is running out of the city by using highway
car, city, highway, run

What are the keywords in the following sentence? A white airplane parked at an airport with a view of a city behind it.
airplane, airport, city, park

What are the keywords in the following sentence? announcer lines up a putt during a round of golf
golf, line, putt, round