Input: Identify the most salient words:

fly in formation over us census designated place

Output: census
designate
formation
place

Input: Identify the most salient words:

sad chimpanzee sitting in a cage

Output: cage
chimpanzee
sit

Input: Identify the most salient words:

demonstrators gather in front of the former embassy .

Output: embassy
front
gather

Input: Identify the most salient words:

mushrooms for sale in the market

Output:
market
mushroom
sale