Monetary vs. Non-monetary assets

[andrevc]

All,
What’s the easiest way you guys have found to distinguish between Monetary and Non-monetary assets and liabilities? I know that the most commonly used accounts can be just memorized, but I wanted to better understand the concept.
For example, PBO would be non-monetary necessarily? How about Prepaid expenses?
Thanks

 

[Harrogath]

I use this:
Moneraty assets: Cash, receivables, marketable securities.
Monetary liabilities: Payables, long-term debt, short-term debt / notes.
I didn’t see PBO as a monetary liability, however, don’t know what others have to say about this.
Prepaid expenses are assets that will be amortized, already paid, so unrealized gains or loses could exist; however nobody accounts this.