Not sure about prepositions, but the articles are often omitted because most Slavic languages don't have articles. http://en.wikipedia.org/wiki/Article_%28gram

Not sure about prepositions, but the articles are often omitted because most Slavic languages don't have articles. http://en.wikipedia.org/wiki/Article_%28grammar%29#Variation_among_languages http://en.wikipedia.org/wiki/Article_%28grammar%29#Variation...