Detailed Instructions: From the given sentence, extract the phrase (often noun or verb) that carries the given relationship. The generated phrase should be present in the sentence.
Q: Given Relationship: 'run on', Sentence: 'Skype for Pocket PC 1.0 enables cross-platform voice calls to other Skype users running Skype for Windows , Skype for Linux , or Skype for Mac OS X .'
A:
running