Input: Identify the most salient words:

black butterfly pollinating flowers in a sunny day

Output: day
flower
pollinate

Input: Identify the most salient words:

A airplane parked at an airport on a tarmac.

Output: airplane
airport
park
tarmac

Input: Identify the most salient words:

a close up of a statue of a zebra in a field

Output: field
statue
zebra

Input: Identify the most salient words:

long scenic road bridge with several lanes with raised sections and fencing in wide mouth

Output:
fence
lane
mouth
raise
section