Input: Identify the most salient words:

Smiles spread across their faces.

Output: face
smile
spread

Input: Identify the most salient words:

sun breaking through the clouds on a gloomy day

Output: break
day
sun

Input: Identify the most salient words:

fishing boat in the harbor of island

Output: boat
harbor
island

Input: Identify the most salient words:

a hydro electric dam being built by country

Output:
build
country
dam