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: The piston starts at the top, the intake valve opens, and the piston moves down to let the engine take in a cylinder-full of air and gasoline. Then the piston moves back up to compress this fuel/air mixture. Compression makes the explosion more powerful. When the piston reaches the top of its stroke, the spark plug emits a spark to ignite the gasoline. The gasoline charge in the cylinder explodes, driving the piston down. Once the piston hits the bottom of its stroke, the exhaust valve opens and the exhaust leaves the cylinder to go out the tailpipe.

SOLUTION: piston ,air ,gasoline ,spark ,explosion ,exhaust

PROBLEM: You must decide the purpose of the satellite. You must draw up a plan to what kind of orbit the satellite will travel. You make preparations for the rocket that will travel into space. Prepare the crew that will send it there. You begin the countdown date for the rocket. And then you send the rocket carrying the satellite into space. Once in orbit the satellite will be placed where it was planned.

SOLUTION: satellite ,rocket

PROBLEM: Fuel is converted to energy when air and petrol mix. The car engine burns the mix of air and petrol. Hot gas from the burning pushes the pistons. The resulting energy powers the crankshaft. Crankshaft powers the gears. The gears make the wheels roll.

SOLUTION:
air ,petrol; fuel ,energy ,hot gas