1. Articles include indefinite articles, definite articles, negative articles, some articles and zero articles, of which zero article refers to the situation without articles.
2. The definite article (for example, the in English) is used to define that the noun after the article is a specific thing;
3. The indefinite article (for example, a/an in English) is used to indicate that the noun after the article refers to one of a certain class of specific things, but it does not matter which one is;
4. Some articles (such as du/delta in French) are used to indicate that the quantity of nouns after the article is uncertain;
5. The negative article (for example, kein in German) is used to indicate that the noun after the article does not exist.
6. Zero article refers to the situation where no article is used.
7. In addition, in some languages (such as French), the masculine and feminine forms of the same noun, the singular and plural forms have the same pronunciation. Through the use of different articles in the front, listeners can distinguish different forms of the noun.
8. Article is a kind of function word, which is not stressed in a sentence and cannot be used independently. It can only be put together with a noun to help explain the person or thing that the noun refers to. There is no article in Chinese.