Theme: Article Plan: Artical types Crosslinguistic variation

Indefinite articles

Indefinite articles typically arise from adjectives meaning one. For example, the indefinite articles in the Romance languages—e.g., un, una, une—derive from the Latin adjective unus. Partitive articles, however, derive from Vulgar Latin de illo, meaning (some) of the.
The English indefinite article an is derived from the same root as one. The -n came to be dropped before consonants, giving rise to the shortened form a. The existence of both forms has led to many cases of juncture loss, for example transforming the original a napron into the modern an apron.
The Persian indefinite article is yek, meaning one.

Using Articles

What is an article? Basically, an article is an adjective. Like adjectives, articles modify nouns.
English has two articles: the and a/an. The is used to refer to specific or particular nouns; a/an is used to modify non-specific or non-particular nouns. We call the the definite article and a/an the indefinite article.
the = definite article
a/an = indefinite article
For example, if I say, "Let's read the book," I mean a specific book. If I say, "Let's read a book," I mean any book rather than a specific book.
Here's another way to explain it: The is used to refer to a specific or particular member of a group. For example, "I just saw the most popular movie of the year." There are many movies, but only one particular movie is the most popular. Therefore, we use the.
"A/an" is used to refer to a non-specific or non-particular member of the group. For example, "I would like to go see a movie." Here, we're not talking about a specific movie. We're talking about any movie. There are many movies, and I want to see any movie. I don't have a specific one in mind.
Let's look at each kind of article a little more closely.

INDEFINITE ARTICLES: A AND AN

"A" and "an" signal that the noun modified is indefinite, referring to any member of a group. For example:

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  "My daughter really wants a dog for Christmas." This refers to any dog. We don't know which dog because we haven't found the dog yet.
  
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  "Somebody call a policeman!" This refers to any policeman. We don't need a specific policeman; we need any policeman who is available.
  
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  "When I was at the zoo, I saw an elephant!" Here, we're talking about a single, non-specific thing, in this case an elephant. There are probably several elephants at the zoo, but there's only one we're talking about here.
  

REMEMBER, USING A OR AN DEPENDS ON THE SOUND THAT BEGINS THE NEXT WORD. SO...

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