What are the keywords in the following sentence? a man relaxes on the grass in a park
grass, park, relax

What are the keywords in the following sentence? man skips past rugby player during the pool match .
match, player, skip

What are the keywords in the following sentence? i like the placement of this tattoo
like, placement, tattoo

What are the keywords in the following sentence? biological species curled up at dusk to sleep for the evening in a cold winter snow
curl, dusk, sleep, snow, specie