Source: http://dcc.dickinson.edu/grammar/latin/agreement-adjectives
Timestamp: 2019-04-19 19:14:08+00:00

Document:
285. Adjectives are either attributive or predicate.
An attributive adjective simply qualifies its noun without the intervention of a verb or participle, expressed or implied.
All other adjectives are called predicate adjectives.
Three farms are handed over to Capito as his own.
They formed a plan full of villany.
Note— A predicate adjective may be used with sum or a copulative verb (§ 283); it may have the construction of a predicate accusative after a verb of naming, calling, or the like (§ 393, Note); or it may be used in apposition like a noun (§ 282.b).
286. Adjectives, Adjective Pronouns, and Participles agree with their nouns in Gender, Number, and Case.
Note— All rules for the agreement of adjectives apply also to adjective pronouns and to participles.
a. With two or more nouns the adjective is regularly plural, but often agrees with the nearest (especially when attributive).
I enjoy all Cæsar's favor and resources.
Juba and Labienus were taken.
b. A collective noun may take an adjective of a different gender and number agreeing with the gender and number of the individuals implied (synesis, § 280.a).
Several colonies were planted (led out) [of men] called Old Latins.
a large part [of the women] were seized.
Note— A superlative in the predicate rarely takes the gender of a partitive genitive by which it is limited.
The dolphin is the swiftest [creature] of creatures.
An attributive adjective agrees with the nearest noun.
A predicate adjective may agree with the nearest noun, if the nouns form one connected idea.
a noise of assent was made (noise and murmur).
Note— This is only when the copula agrees with the nearest subject (§ 317.c).
But generally, a predicate adjective will be masculine, if nouns of different genders mean living beings; neuter, if things without life.
then his wife and children embraced him.
Labor and delight are bound together by a certain natural alliance.
If nouns of different genders include both living beings and things without life, a predicate adjective is sometimes masculine (or feminine), sometimes neuter, and sometimes agrees in gender with the nearest if that is plural.
The king and the royal fleet set out together.
By nature, a free state and a king are hostile.
that the ambassadors and the replies of the oracle should be waited for.
a. Two or more abstract nouns of the same gender may have a predicate adjective in the neuter plural (cf. § 289.c, below).
Folly, rashness, and injustice are [things] to be shunned.
288. Adjectives are often used as nouns (substantively), the masculine usually to denote men or people in general of that kind, the feminine women, and the neuter things.
Note— The plural of adjectives, pronouns, and participles is very common in this use. The singular is comparatively rare except in the neuter (§ 289.a and c, below) and in words that have become practically nouns.
a. Certain adjectives have become practically nouns, and are often modified by other adjectives or by the possessive genitive.
b. When ambiguity would arise from the substantive use of an adjective, a noun must be added.
c. Many adjectives are used substantively either in the singular or the plural, with the added meaning of some noun which is understood from constant association.
Note— These adjectives are specific in meaning, not generic like those in § 288. They include the names of winds and months (§ 31).
For nouns used as adjectives, see § 321.c.
For adverbs used like adjectives, see § 321.d.
289. Neuter adjectives are used substantively in the following special senses.
a. The neuter singular may denote either a single object or an abstract quality.
b. The neuter plural is used to signify objects in general having the quality denoted, and hence may stand for the abstract idea.
c. A neuter adjective may be used as an appositive or predicate noun with a noun of different gender (cf. § 287. a, above).
The wolf [is] a grievous thing for the fold.
Woman is ever a changing and fickle thing.
Death seems to me to be an evil.
d. A neuter adjective may be used as an attributive or a predicate adjective with an infinitive or a substantive clause.
It is one thing to be unwilling that Cæsar should err, another to be unwilling that he should pity.
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.
He was the first to come (came first).
They were glad to hear.
He was often at Rome.
May you return late to heaven.

References: § 280
 § 289
 § 288
 § 321
 § 321
 § 287