Given a fact, create a question that can be answered using the fact. Construct the question such that it is unambiguous, has a unique answer and the answer can be given using the fact.

Fact: a valley is formed by a river flowing
In what way are valleys formed?

Fact: as light pollution increases , seeing the stars will be harder
A quiet desert town will see more _____ than a big city will.?

Fact: nerves can be used to feel heat and pressure on the skin

If your hand is being burned on a stove?