Is this really a problem or you made it up, because I don't think that is a question :(
Answer:
You are speaking Indonesian
Explanation:
Is what I do with world languages.
The metaphor in this statement is "the great millstone" it kind of qualification word it express how big the time was.
But in reality, millstone doesn't even have a relationship with the time.
So "the great millstone" is a metaphor.
The answer is:
False.
You are welcome for the answer.