How to change the language file in K2 component

Hello, I am trying to change the text "You are here", "Written by", "font size", "Rate this item", "Read 2 times", "Latest from", "More in this category", "back to top", etc..of the articles . I am using *k2 component in the League News template on joomla 2.5. I understand that the language files have to be edited but there are many languages files...one in Administrator folder, one in the root folder.etc. I need to change all the site into Spanish language. Please kindly specify which folder and what file and line to edit precisely. Thanks a lot.

Language files are usually named according to element that they came from. So if one has k2 in name - it will translate k2 specific element, same with our template, components, plugins etc.
If you will have any problems with few lines, please tell me which and I will help you find them.