What are the keywords in the following sentence? Three large giraffes are running across the plains.
giraffe, plain, run

What are the keywords in the following sentence? a small boat passing beneath the arches of renaissance structure
arch, boat, pass

What are the keywords in the following sentence? A construction worker operates a vehicle.
operate, vehicle, worker

What are the keywords in the following sentence? A building with a clock above the main entrance.
building, clock, entrance