What are the keywords in the following sentence? passengers awaiting their baggage at the carousel in south airport
airport, baggage, passenger

What are the keywords in the following sentence? cheap colourful sunglasses for sale in a stall
sale, stall, sunglass

What are the keywords in the following sentence? A skateboarder rides on the side of a large pipe.
pipe, ride, side

What are the keywords in the following sentence? a little tree growing in the grass on top of cliff
cliff, grass, grow, top, tree