TASK DEFINITION: In this task, you are given a paragraph, and your job is to generate comma-separated entities present in the given paragraph. Generate entities from a given passage in such a way that (i) they are present in the paragraph, (ii) they are non-duplicate, (iii) they underwent a state change during the process. Avoid creating entities that (i) aren't present in the process paragraph and (ii) aren't significant. 
PROBLEM: Trash is placed into a garbage container in the house. The trash is moved to a centralized container for the house. Trash is picked up by a sanitation company. The trash is combined in a large truck with trash from all around the city. The truck goes to the landfill. The truck dumps the trash into the landfill. 

SOLUTION: trash ,truck 

PROBLEM: An eagle flys along. The eagle spots a mouse on the ground. The eagle swoops down. Catches the mouse in its talons. The eagle has a meal. 

SOLUTION: mouse ,meal 

PROBLEM: Muscles work by expanding and contracting. A muscle fiber gets a signal from its nerve. Proteins and chemicals release energy to either contract the muscle or relax it. When the muscles contracts the bones connected to he muscle are pulled closer together. When the muscle relaxes the bones move farther apart. 

SOLUTION:
signal ,energy