TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: The action of flushing the toilet, performed multiple times daily, is the single biggest use of water in the home.

SOLUTION: What action, performed multiple times daily, is the single biggest use of water in the home?

PROBLEM: Mesoderm type of cell layer do flatworms have.

SOLUTION: What type of cell layer do flatworms have?

PROBLEM: Birds build nests to safe place.

SOLUTION:
Why do birds build nests?