Two principal motives for a clausal predicate are strengthened attribution and related/sababī predication. «Zayd qāma» strengthens the assertion through the returning subject pronoun. «Zayd abūhu qāʾim» reports about Zayd via the state of his father.
A nominal predicate-clause tends toward stability, while a verbal clause highlights an occurrence and time. An adverbial predicate expresses location economically, with a grammatical dispute about whether to supply an implicit verb or participle.
The next distinct discussion concerns delaying or fronting the predicate and the rhetorical effects of changing its position.