Learning Spanish for free might depend on the definition but the best and fastest way in my opinion is to immerse yourself in the culture, speak to people, shop, chat around the dinner table and so on - all in Spanish of course. This is assuming that you're visiting Medellin or some other Spanish speaking part of the world.
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- Learn Spanish on-line for free, using interactive audio/visual lessons.
I remember taking Spanish for my International Baccalaureate (high-school equivalent) in England and the truth is, it didn't sink in. Now that I'm speaking it at times daily for weeks or months, it's completely different. Granted, my grammar and vocabulary need work but I'm convinced it's a far more efficient way of learning a language.
Reading newspapers is another approach - online for example. Check out
El Colombiano,
the main newspaper of Medellin to learn vocabulary.
Babel Fish or
Google Translate
are great resources for translating text fairly accurately. Copy and paste the text into their translation tools and learn some of the words.
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