Input: Identify the most salient words:

waterfalls flow into river in a deep valley surrounded by mountains

Output: flow
river
valley
waterfall

Input: Identify the most salient words:

A white piece of pizza served on a plate

Output: piece
pizza
serve

Input: Identify the most salient words:

a firefighter tries to extinguish as much flame as possible inside a burning tree trunk on thursday night

Output: extinguish
firefighter
flame
night

Input: Identify the most salient words:

A train coming out of a tunnel and rounding a corner.

Output:
come
corner
round
train