The Allen and Greenough is still under construction;
so some links may not work quite the way you would expect.
Adjectives with Adverbial Force.
290. An adjective, agreeing with the subject or
object, is often used to qualify the action of the verb, and so has the
force of an adverb: -
- prímus venit, he was the first to come (came first).
- núllus dubitó, I no way doubt.
- laetí audiére, they were glad to hear.
- erat Rómae
frequéns (Rosc. Am. 16), he was often at Rome.
- sérus in caelum redeás (Hor. Od. i. 2. 46),
mayst thou return late to heaven.