Possessive and Demonstrative Pronouns - Pronombres Demostrativos y Posesivos (Médicos)

Whereas demonstrative adjectives modify a noun (e.g. este carro, this car) by explaining which car you are talking about, demonstrative pronouns replace a noun altogether (e.g. ése, that one).

Mi bicicleta es mejor que aquélla. - My bicycle is better than that one.
Estas manzanas son mejores que aquéllas. - These apples are better than those.

It is important to pronounce the demonstrative pronouns correctly. Practice saying them and pay special attention to the placement of the accents.

Demonstrative pronouns can also be used to express the former and the latter in English.

Maria y Irma son chicas bonitas. Éste de México, aquél de Guatemala.
Mary and Irma are beautiful girls. The former from Mexico, the latter from Guatemala.

The following chart will help you decide which demonstrative pronoun you will need to use.

We use the Possessive Pronouns when we want to substitute a group of words that are indicating a possession relation.

Éste es mi libro. - This is my book.

In this example, we can substitute "mi libro" (my book) for the possessive pronoun "mío" (mine) and we would have:

Éste es mío. - This is mine
or
Este libro es mío. - This book is mine.

In Spanish the possessive pronouns are normally formed with the definite article and "mío", "tuyo", or "suyo".

Mi coche es rápido. - My car is fast.
El mío es más rápido. - Mine is faster.

In this example, "el mío" (mine) substitutes "mi coche" (my car) and it is formed by the definite article masculine, singular "el" (the) and the pronoun "mío" (mine)*