What are the keywords in the following sentence? window with stained glass in the style .
glass, style, window

What are the keywords in the following sentence? A human is placing a toy train on a toy track.
place, track, train

What are the keywords in the following sentence? armed force deployed in support of event provided members of a class
event, force, provide, support

What are the keywords in the following sentence? a herd of sheep on pasture eating grass on a sunny fall day under blue skies
grass, sheep, sky