TASK DEFINITION: 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.
PROBLEM: Who invented the system of latitudes and longitudes in 2nd century a.d?

SOLUTION: Who invented the system of latitudes and longitudes, measuring latitudes using the island of Rhodes in 2nd century a.d?

PROBLEM: Where is the x factor final 2017 filmed?

SOLUTION: In what building is the x factor final 2017 filmed?

PROBLEM: When did construction start on the great wall of china?

SOLUTION:
When did construction start on the first versions of the great wall of china?