Gerund and Gerundive.

1. _The Gerund is a verbal noun and is used only in the genitive,
dative, accusative, and ablative singular. The constructions of these
cases are in general the same as those of other nouns._

2. _The Gerundive is a verbal adjective and must be used instead of
gerund + object excepting in the genitive and in the ablative without
a preposition. Even in these instances the gerundive construction is
more usual._

_407._ RULE. Gerund or Gerundive of Purpose. _The accusative of the
gerund or gerundive with_ /ad\, _or the genitive with /causa\[3] (= for
the sake of), is used to express purpose._

GERUND GERUNDIVE
Ad audiendum venerunt or Ad urbem videndam venerunt or
Audiendi causa venerunt Urbis videndae causa venerunt
_They came to hear_ _They came to see the city_

[Footnote 3: /causa\ always _follows_ the genitive.]

NOTE. These sentences might, of course, be written with the subjunctive
of purpose,--/venerunt ut audirent\; /venerunt ut urbem viderent\. In
short expressions, however, the gerund and gerundive of purpose are
rather more common.

_408._ We have learned that the word denoting the owner or possessor of
something is in the genitive, as, /equus Galbae\, _Galba's horse._ If,
now, we wish to express the idea _the horse is Galba's_, Galba remains
the possessor, and hence in the genitive as before, but now stands in
the predicate, as, /equus est Galbae\. Hence this is called the
predicate genitive.

_409._ RULE. Predicate Genitive. _The possessive genitive often stands
in the predicate, especially after the forms of /sum\, and is then
called the predicate genitive._

_410._ IDIOMS

alicui negotium dare, _to employ someone_
(lit. _to give business to some one_)
novis rebus studere, _to be eager for a revolution_
(lit. _to be eager for new things_)
rei militaris peritissimus, _very skillful in the art of war_
se suaque omnia, _themselves and all their possessions_

_411._ EXERCISES

I. 1. Caesar cum in Gallia bellum gereret, militibus decimae legionis
maxime favit quia rei militaris peritissimi erant. 2. Sociis negotium
dedit rei frumentariae curandae. 3. Legati non solum audiendi causa sed
etiam dicendi causa venerunt. 4. Imperator iussit exploratores locum
idoneum munindo reperire. 5. Nuper hae gentes novis rebus studebant;
mox iis persuadebo ut Caesari se suaque omnia dedant. 6. Iubere est