Input: Identify the most salient words:

frog sitting on leaf with lily in the pond

Output: frog
leaf
pond

Input: Identify the most salient words:

an astronaut drifting in space is rescued by a space shuttle orbiting earth

Output: drift
earth
orbit
shuttle
space

Input: Identify the most salient words:

swim with dolphins and snorkel the coral reef

Output: reef
snorkel
swim

Input: Identify the most salient words:

the exhibit attracts the attention of local people and tourists

Output:
attention
attract
tourist