

The book is upon the table.
Indicates a position on a surface or in relation to something.
The cat is upon the roof.
The painting hangs upon the wall.
The keys are upon the counter.
upon request
upon arrival
upon reflection
on
over
above
The success of the project depends upon teamwork.
In a position or situation that is dependent on something else.
Her happiness depends upon her health.
The outcome relies upon their decision.
Our plans are based upon the weather.
depends upon circumstances
depends upon conditions
depends upon factors
contingent on
conditional on
reliant on