Indefinite Adjectives

Here are the most common indefinite adjectives along with their common translations and sample sentences:

• algún, alguna, algunos, algunas — some, a few, any — Algún día voy a España. Some day, I'm going to Spain. Tiene algunos libros. He has some books.
• cada — each, every — Cada día voy a la oficina. I go to the office every day. Tenemos un libro por cada tres estudiantes. We have one book for every three students. (Cada is invariable, making no changes with number or gender.)

• cierto, cierta, ciertos, ciertas — certain, specific — Quiero comprar cierto libro. I want to buy a certain book. Ciertas estudiantes fueron a la biblioteca. Certain students went to the library. (This adjective is not preceded by un or una. When used after a noun, the word means "true" or "accurate.")
• cualquier, cualquiera — any, whatever, whichever, whoever, whomever — Cualquier estudiante puede aprobar el examen. Any student can pass the test. Estudia a cualquier hora. He studies at whatever time. Podemos viajar a una ciudad cualquiera. We can travel to any old city. (A plural form, cualesquiera (both masculine and feminine) exists but is seldom used. When cualquiera(masculine or feminine) is used after the noun, it emphasizes that the specific identity of the noun is unimportant, somewhat like "any old" in English.) Note that through apocopation, cualquiera is shortened to cualquier when it comes before a noun.
• ningún, ninguna — no, not any — No quiero ningún libro. I don't want any books. Ninguna mujer puede salir. No woman can leave. (As in the first example, a double negative" can be required in Spanish when this adjective is used before the object of a verb. The plural forms, ningunos andningunas, exist but are seldom used, even though an English plural form is used in translation.)
• otro, otra, otros, otras — another, other — Quiero otro lápiz. I want another pencil. Otra persona lo haría. Another person would do it. Quiero comprar los otros libros. I want to buy the other books. (This adjective is not preceded by un or una.)

• todo, toda, todos, todas — each, every, all, all of — Todo estudiante conoce al señor Smith.Every student knows Mr. Smith. Corrieron a toda velocidad. They ran at full speed. Todos los estudiantes conocen al señor Smith. All of the students know Mr. Smith. Durmió toda la noche.She slept all night. (When it means "each" or "every," todo/toda is used in singular form before the noun. When it means "all of," the adjective precedes the entire noun phrase, as in the examples.
• varios, varias — several — Compró varios libros. She bought several books. Hay varias soluciones. There are several solutions. (In singular form and sometimes in the plural form, the adjective also can mean "varied," "different" or "various.")

Note that while some of these adjectives can be translated as "any," the English word "any" is often left untranslated into Spanish: ¿Tienen ustedes libros? Do you have any books? No tenemos libros. We don't have any books.

http://spanish.about.com/od/adjectives/a/indef_adjective.htm