What are the keywords in the following sentence? An airport tarmac with jets parked on top of it.
jet, park, tarmac, top

What are the keywords in the following sentence? deforestation may be the largest threat to lost cities hidden within the rainforest .
city, hide, lose

What are the keywords in the following sentence? divers entering the sea from the boat
boat, diver, sea

What are the keywords in the following sentence? The player tries to prevent his opponent from scoring.
player, prevent, scoring