That

As an adjective

The translations ese and aquel agree in number and gender with the nouns they modify; that is translated by ese, esa, aquel, aquella, and those by esos, esas, aquellos, aquellas, depending on the meaning being translated, and what follows:

•  that book/magazine = ese libro/esa revista or aquel libro/aquella revista
•  those books/magazines = esos libros/esas revistas or aquellos libros/aquellas revistas

As a pronoun

Again, the translations ése and aquél agree in number and gender with the nouns they are standing for; that is translated by ése, ésa, aquél, aquélla, and those by ésos, ésas, aquéllos, aquéllas, depending on the meaning being translated, and what is being referred to:

•  that (one) is yours = ése or aquél es el tuyo
•  those were the best years of my life = ésos or aquéllos fueron los mejores a?os de mi vida

? When that as a pronoun is used to refer to something which is not specified for gender, it is translated by the neuter eso or aquello, according to context:

•  what’s that? = ?qué es eso?
•  why did he do that? = ?por qué hizo eso?
•  what’s that over there? = ?qué es aquello que se ve allá?

Sometimes it is not translated at all:

•  that’s incredible! = ?es increíble!

For more examples and particular usages see the entries for that

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