éstas

Éstas is a Spanish demonstrative pronoun. It is the feminine plural form of the demonstrative adjective and pronoun "este." Demonstrative pronouns in Spanish, like "éste," "ésta," "estos," "estas," "ese," "esa," "esos," "esas," "aquel," "aquella," "aquellos," and "aquellas," are used to point out or identify nouns that are near the speaker, or at a distance from the speaker and the listener, or far from both. "Éstas" specifically refers to feminine nouns that are close to the speaker.

For example, in the sentence "Éstas son mis llaves" (These are my keys), "éstas" is used to refer to the feminine plural noun "llaves" (keys) which are presumably near the speaker. It functions as a pronoun, replacing the noun itself. If the noun were present, it would be used as a demonstrative adjective, for instance, "estas llaves." The accent mark on "éste" and its variations (ésta, éstos, éstas) was historically used to distinguish them from the conjunction "este" (this/that) and the indefinite pronouns "ese" and "aquel" when they were not accompanied by a noun. However, the Real Academia Española (RAE) updated its orthographic rules in 2010, and the accent mark is no longer mandatory for demonstrative pronouns when there is no ambiguity. Therefore, "estas" is now the preferred form.