In Estonian grammar, articles play an important role in determining the definiteness or indefiniteness of a noun. Unlike many other languages, Estonian has no indefinite article (like “a” or “an” in English), but it does have a definite article (the equivalent of “the” in English).

The definite article in Estonian is “see” or “too,” depending on the case and number of the noun. For example, “koer” (dog) becomes “see koer” when it is definite, and “koer” when it is indefinite.

The definite article also changes depending on the case of the noun. For example, in the genitive case, “koer” becomes “selle koera” (this dog), and in the plural, it becomes “need koerad” (these dogs).

It is important to note that the definite article is not used with all nouns in Estonian. Some nouns are inherently definite or indefinite, depending on the context. Additionally, there are certain cases (such as the partitive case) where the definite article is not used.

Overall, understanding articles in Estonian grammar is crucial for correctly determining the definiteness or indefiniteness of nouns in a sentence.