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"That one" is a pronoun which is often translated as "ese", and "this one" is a phrase which is often translated as "este". Learn more about the difference between "that one" and "this one" below.
that one(
thaht
wuhn
)A pronoun is a word that stands in for a noun (e.g., she).
a. ese (masculine)
Which of these coats is yours? - That one.¿Cuál de estos abrigos es el tuyo? - Ese.
b. esa (femenine)
Yes, I know that that's your house, but whose is that one?Sí, sé que esa casa es la tuya, pero ¿de quién es esa?
d. aquel (masculine)
Which dress are you talking about? - That one in the window.¿De qué vestido hablas? - Aquel que está en la vidriera.
e. aquella (femenine)
I like this computer, but it's a lot more expensive than that one at the last store.Me gusta esta computadora, pero es mucho más cara que aquella que vimos en la última tienda.
this one(
thihs
wuhn
)A phrase is a group of words commonly used together (e.g., once upon a time).
a. este
He's written a lot of books, but this one is the best.Ha escrito muchos libros, pero este es el mejor.
I like that shirt, but they only have this one in my size.Me gusta esa camisa, pero solo tienen esta en mi talla.