Input: Identify the most salient words:

top cities with longest working hours in the world

Output: city
work
world

Input: Identify the most salient words:

boats moored beside houses on the grand canal

Output: boat
canal
house
moor

Input: Identify the most salient words:

Smoke is coming out of a train engine on the tracks.

Output: engine
smoke
track

Input: Identify the most salient words:

A train carrying cargo driving on train tracks on an overcast day.

Output:
cargo
day
track
train