What are the keywords in the following sentence? heavy thick smoke covering the sky as it billows up from a fire .
billow, fire, sky

What are the keywords in the following sentence? the property is coming on the market for the fifth time
market, property, time

What are the keywords in the following sentence? an old run down bridge crossing a lake
bridge, cross, lake

What are the keywords in the following sentence? A group of people look for things to buy in a market
buy, market, thing