Input: Identify the most salient words:

a conceptual image of an aircraft powered by the new engine .

Output: aircraft
engine
power

Input: Identify the most salient words:

steel studs and concrete floors in the construction of a modern building

Output: building
construction
floor

Input: Identify the most salient words:

pink heart shaped flower growing

Output: flower
heart
shape

Input: Identify the most salient words:

a tractor is pulling agricultural machinery behind it when preparing hay .

Output:
hay
machinery
prepare
tractor