In this task, you're given an ambiguous question (which can be answered in more than one way). Your task is to write a question that clarifies the given question in such a way that the generated question has one unique answer.

When did we become the united states of america?
When, based on evidence, did we begin calling ourselves the united states of america?

Which indian city is known as venice of the east?
What city that is the head of the Alappuzha District in the Indian State of Kerala has been known as "Venice of the East"?

When was it discovered that asbestos was dangerous?

When was it thought to have been first reported that asbestos may be dangerous?