The statement "We need to bring some money, but the amount is indefinite right now. I'll let you know when we are sure." is false.
Why is the statement false?
The statement is false because the speaker says that the amount of money needed is indefinite at the moment, and they will inform you when they are sure about the specific amount.
Given that the amount is truly indefinite, it may be challenging for the speaker to later provide a definite amount.
Therefore, it suggests that the speaker is unsure about the details, making the statement false.