RULES OF SYNTAX 263
. The ablative of a noun or pronoun with a present or perfect parti- iple in agreement is used to express attendant circumstance. This is called
- le ablative absolute. §381.
. I. Descriptions of physical characteristics are expressed by the ablative with a modifying adjective. § 444. . Descriptions involving neither numerical statements nor physical char- acteristics may be expressed by either the genitive or the ablative with a modifying adjective. § 445. . The aJjlative is used to denote in what respect something is true. i^ 398- . The place from which is expressed by a or ab, de, g or ex with the separative ablative. This answers the question Whence.'* Before names of towns, small islands, domus, and rus the preposition is omitted. §§ 264, 266. . Words expressing separation or deprivation require an ablative to complete their meaning. This is called the ablative of separation. § 1 80. . The word expressing the person from whom an action starts, when not the subject, is put in the ablative with the preposition a or ab. This is called the ablative of the personal agent. § 181. . The comparative degree, if quam is omitted, is followed by the separative ablative. § 309. . The time when or within which anything happens is expressed by I he ablative without a preposition. § 275. . I. TYit. place at or in which is expressed by the ablative with in. This answers the question Where .-* Before names of towns, small islands, and riis the preposition is omitted. §§ 265, 266. . Names of towns and small islands, if singular and of the first or second declension, and the word domus express the place in which by the locative. § 268. Gerund and Gerundiot . I . 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 i& those of other nouns. § 406. i . . The gerundive is a verbal adjective and must be used instead of gerund -f object, excepting in the genitive and in the ablative without a preposition. Even in tht*se instances the gerundive construction is more usual. § 406. 2. . The accusative of the gerund or gerundive with ad, or the genitive with cau8&, is used to expcess purpose. § 407.