There is no official rule as to when to use "s/z/v/k" versus "se/ze/ve/ke". The purpose of the -e in prepositions like "se", "ze", "ve" is to make the pronunciation easier when the preposition is placed in front of a word that begins with a consonant or a consonant group that would be difficult to pronounce … Continue reading When to use “s/z/v/k” versus “se/ze/ve/ke in Czech →