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Logic of definite articles
In English, a definite article is mostly used to refer to an object or person that has been previously introduced. For example:
At last they came to a piece of rising ground, from which they plainly distinguished, sleeping on a distant mountain, a mammoth bear.... Then they requested the eldest to try and slip the belt over the bear's head.
— Mark Twain, Life on the Mississippi, appendix D
In this example, a bear becomes the bear because a "mammoth bear" had been previously introduced into the narrative, and no other bear was involved in the story. Only previously introduced subjects like "the bear" or unique subjects, where the speaker can assume that the audience is aware of the identity of the referent (The heart has its reasons) typically take definite articles in English.
By contrast, the indefinite article is used in situations where a new subject is being introduced, and the speaker assumes that the hearer is not yet familiar with the subject:
There was an old woman who lived in a shoe.
— A traditional nursery rhyme
Reflecting its historical derivation from the number word one, the English indefinite article can only be used with singular count nouns. For mass nouns, or for plurals, adjectives or adjective phrases like some or a few substitute for it. In English, pronouns, nouns already having another non-number determiner, and proper nouns usually do not use articles. Otherwise in English, unlike many other languages, singular count nouns take an article; either a, an, or the.[3] Also in English word order, articles precede any adjectives which modify the applicable noun.[citation needed]
In French, the masculine definite article le (meaning the) is contracted with a following word if that word begins with a vowel sound. When the French words de and le are to be used sequentially (meaning of the), the word du is used instead, in addition to the above mentioned use of du as a partitive article.
In various languages other than English, the form of the article may vary according to the grammatical gender, number or case of the noun it combines with. Many languages do not use articles at all, and may use other ways of indicating old vs. new information, such as topic-comment constructions