The ablative absolute is a Latin grammatical construct that accounts for a phrase that is set apart from the main subject and verb of the sentence. In many ways, this phrase acts as a modifier for the main part of the sentence, but it can be removed without affecting the grammatical structure of the sentence. It is known as the ablative absolute because the modifying words in the phrase are in the Latin ablative case. When translated into English, this type of phrase is often rearranged by using prepositions that would not have been included in the original Latin.
There are many ways in which the Latin and English languages differ in their accounting for particular grammatical structures. One of those instances involves the ways that separate, modifying phrases in a sentence are treated. In English, these phrases are usually set apart by a comma from the main section of the sentence, along with the use of prepositions to help distinguish them. By contrast, Latin uses the ablative absolute as a way to set these phrases apart from the rest of the sentence.
In general, a phrase that requires an ablative absolute in Latin either indicates a time frame separate from the main phrase, or reflects something that caused the main part of the sentence to occur. Whatever words form the crux of the phrase are placed in the ablative case. Normally, the ablative case in Latin is the result of a prepositional phrase, but no prepositions are added in Latin when these phrases are used.
As an example, consider the English sentence, "Once he sent the girl to school, he was sad." The Latin translation for the first words of the opening phrase would be "Puella missa." "Puella" is the ablative case of the Latin word for "girl", and "missa" is the past participle form in the ablative case of the Latin word for "to send." When translated into English, the word "once" is included to express the time frame, which is implied in Latin by the ablative absolute. A literal translation of the Latin would be "the girl having been sent."
Other circumstances may require the use of this grammatical construct in Latin. When the English verb "to be" is included in conjunction with a noun, it would call for the ablative case for the noun; the form of the verb "to be" is implied in Latin, since the language has no perfect or present participle for its corresponding word "esse." It is important to realize that any phrase requiring the ablative absolute translation must have a grammatical connection to the rest of the sentence, even if the phrase completes its meaning.