Prainstructed or Preinstructed: How To spell?

The word Prainstructed is misspelled against Preinstructed, which is past tense of "Preinstruct"

Word contains consecutive vowels 'EI' in between alphabets pr & nstructed is misspelled as 'AI'
Wrong Spelling:  pr-ai-nstructed 
Correct Spelling:  pr-ei-nstructed 
Check more misspelled words of Preinstructed to spell it correct.