The apostrophe is almost never used in modern Spanish. Its use is limited to words of foreign origin (usually names) and, very rarely, poetry or poetic literature. Spanish students should not imitate the common uses of the apostrophe in English.
Here are some examples of uses of the apostrophe for words or names of foreign origin:
- Me siento vieja. Pero, c'est la vie. I feel old. But such is life.
- Un jack-o'-lantern es una calabaza tallada a mano, asociada a la festividad de Halloween. A jack-o'-lantern is a pumpkin carved by hand and associated with Halloween festivities.
- Sinéad Marie Bernadette O'Connor es una cantante nacida en Dublín, Irlanda. Sinéad Marie Bernadette O'Connor is a singer born in Dublin, Ireland.
- McDonald's ofrece una gran variedad de alimentos de alta calidad. McDonald's offers a big variety of high-quality foods.
Note that in all the above cases the words would be recognized as being of foreign origin. In the first two cases, the use of the words with apostrophes would be seen as a Gallicism and Anglicism, respectively.
The apostrophe can occasionally be found in centuries-old poetry or literature as a way of showing that letters have been omitted. Such use is very rarely found in modern writing, and then only for literary effect.
- Nuestras vidas son los ríos / que van a dar en la mar, / qu'es el morir. Our lives are the rivers / that flow to give to the sea, / which is death. (From Coplas de Don Jorge Manrique por la muerte de su padre, 1477.)
- ¿ ... qué me ha de aprovechar ver la pintura / d'aquel que con las alas derretidas ...? ... what could it help me to see the painting of that one with the melted wings ...? (From the 12th sonnet of Garcilazo de la Vega, c. 1500-1536.)
According to the Royal Spanish Academy, the apostrophe should not be used in the following instances, which are considered Anglicisms:
- To shorten years, such as using '04 for 2004. Simply 04 can be used instead.
- To make plurals.