A compound subject is one which consists of more than one
noun.
Examples:
A clean
driving licence, sales experience and team spirit are essential. The pigeon
and the falcon fell from view. My wife
and I cannot attend unfortunately. ("I" is a noun - a
pronoun.)
Interactive example:
Neither the Army nor the Police had any
suitable vehicles. [show me the compound subject]
It is possible to end a
compound subject with a comma to group it neatly for your readers. This is not a popular practice amongst grammarians.
However, if you think it
helps, do it.