Overpasing or Overpassing: How To spell?
The word Overpasing is misspelled against Overpassing, which is present continuous of "Overpass"
Overpassing has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings overpa & ing which should not be misspelled with single 'S'
Wrong Spelling:  overpa-s-ing  Correct Spelling:  overpa-ss-ing 
Find more wrongly spelled words of Overpassing to spell it well.