Englishfor English speakers
upon
Preposition
—
on or onto
The police were called upon to save him.
The snow fell gently upon the lake.
—
going to happen
Christmas is almost upon us.
—
at (a time)
Upon his death, she became the owner of the store.
compulsion
Noun
—
If you have a compulsion to do something, you really want to do it even though there is no good reason.
—
If someone is under compulsion to do something, they are being forced to do it.