INFINITIVE
Pres.  velle             no:lle              ma:lle
Perf.  voluisse          no:luisse           ma:luisse

PARTICIPLE
Pres. vole:ns, -entis no:le:ns, -entis ——­]

380. Observe the following sentences: 

  1.  Magistro laudante omnes pueri diligenter laborant, with the
  teacher praising, or since the teacher praises, or the teacher
  praising, all the boys labor diligently.

  2.  Caesare ducente nemo progredi timet, with Caesar leading, or
  when Caesar leads, or if Caesar leads, or Caesar leading, no one
  fears to advance.

  3.  His rebus cognitis milites fugerunt, when this was known, or
  since this was known, or these things having been learned, the
  soldiers fled.

  4.  Proelio commisso multi vulnerati sunt, after the battle had
  begun, or when the battle had begun, or the battle having been
  joined, many were wounded.

a. One of the fundamental ablative relations is expressed in English by the preposition with (cf.  Sec. 50).  In each of the sentences above we have a noun and a participle in agreement in the ablative, and the translation shows that in each instance the ablative expresses attendant circumstance.  For example, in the first sentence the circumstance attending or accompanying the diligent labor of the boys is the praise of the teacher.  This is clearly a with relation, and the ablative is the case to use.

b. We observe, further, that the ablative and its participle are absolutely independent grammatically of the rest of the sentence.  If we were to express the thought in English in a similar way, we should use the nominative independent or absolute.  In Latin the construction is called the Ablative Absolute, or the Ablative with a Participle.  This form of expression is exceedingly common in Latin, but rather rare in English, so we must not, as a rule, employ the English absolute construction to translate the ablative abolute.  The attendant circumstance may be one of time (when or after), or one of cause (since), or one of concession (though), or one of condition (if).  In each case try to discover the precise relation, and tranlate the ablative and its participle by a clause which will best express the thought.

381. RULE.  Ablative Absolute. The ablative of a noun or pronoun with a present or perfect participle in agreement is used to express attendant circumstance.

NOTE 1.  The verb sum\ has no present participle.  In consequence we often find two nouns or a noun and an adjective in the ablative absolute with no participle expressed; as, te duce\, you (being) leader, with you as leader; patre infirmo\, _my father_ (being) _weak_.