Given scientific fact as input, generate the question from this fact such that it can be answered from the input.

10 million years long can a large star be on the main sequence stage.
How long can a large star be on the main sequence stage?

Potential energy type of energy is possessed by autumn leaves before they fall.
What type of energy is possessed by autumn leaves before they fall?

The large central vacuole store water.
What does the large central vacuole do?