13. The Article. Difficulties of the study of articles.

The articles in English are the definite article the and the indefinite articles a and an (and sometimes some). Use of the definite article implies that the speaker assumes the listener knows the identity of the noun's referent (because it is obvious, because it is common knowledge, or because it was mentioned in the same sentence or an earlier sentence). Use of an indefinite article implies that the speaker assumes the listener does not have to know the identity of the referent. In some noun phrases no article is used.

Articles are a special case of determiners in English; for information about this class as a whole, see English determiners.

The rules of English grammar require that in most cases a noun, or more generally a noun phrase, must be "completed" with a determiner to clarify what the referent of the noun phrase is.[1] The most common determiners are the articles the and a(n), which specify the presence or absence of definiteness of the noun. Other possible determiners include words like this, my, each and many – see English determiners. There are also cases where no determiner is required, as in the sentence John likes fast cars. Or the sentence Bob likes cool trains.

The definite article the is used when the referent of the noun phrase is assumed to be unique or known from the context. For example, in the sentence The boy with glasses was looking at the moon, it is assumed that in the context the reference can only be to one boy and one moon. However, the definite article is not used:

with generic nouns (plural or uncountable): cars have accelerators, happiness is contagious, referring to cars in general and happiness in general (compare the happiness I felt yesterday, specifying particular happiness);

with many proper names: John, France, London, etc.

The indefinite article a (before a consonant sound) or an (before a vowel sound) is used only with singular, countable nouns. It indicates that the referent of the noun phrase is one unspecified member of a class. For example, the sentence An ugly man was smoking a pipe does not refer to any specifically known ugly man or pipe.

No article is used with plural or uncountable nouns when the referent is indefinite (just as in the generic definite case described above). However, in such situations, the determiner some is often added (or any in negative contexts and in many questions). For example:

There are apples in the kitchen or There are some apples in the kitchen;

We do not have information or We do not have any information;

Would you like tea? or Would you like some tea? and Would you like any tea? or Would you like some good tea?

Additionally, articles are not normally used:

in noun phrases that contain other determiners (my house, this cat, America's history), although one can combine articles with certain other determiners, as in the many issues, such a child (see English determiners: Combinations of determiners).

with pronouns (he, nobody), although again certain combinations are possible (as the one, the many, the few).

preceding noun phrases consisting of a clause or infinitive phrase (what you've done is very good, to surrender is to die).

If it is required to be concise, e.g. in headlines, signs, labels, and notes, articles are often omitted along with certain other function words. For example, rather than The mayor was attacked, a newspaper headline might say just Mayor attacked.

For more information on article usage, see the sections Definite article and Indefinite article below. For more cases where no article is used, see Zero article in English.

The only definite article in English is the word the, denoting person(s) or thing(s) already mentioned, under discussion, implied, or otherwise presumed familiar to the listener or reader. The is the most commonly used word in the English language.

"The" can be used with both singular and plural nouns, with nouns of any gender, and with nouns that start with any letter. This is different from many other languages which have different articles for different genders and/or numbers.

The indefinite article of English takes the two forms a and an. Semantically they can be regarded as meaning "one", usually without emphasis. They can be used only with singular countable nouns; for the possible use of some (or any) as an equivalent with plural and uncountable nouns, see Use of some below.