Hightening or Heightening: How To spell?

The word Hightening is misspelled against Heightening, which is present continuous of "Heighten"

Word contains consecutive vowels 'EI' in between alphabets h & ghtening is misspelled as 'I' as letter 'E' is phonetically igno
Wrong Spelling:  h-i-ghtening 
Correct Spelling:  h-ei-ghtening 
Find more wrongly spelled words of Heightening to spell it well.