Original sentence: The Swedish alphabet is a 29-letter alphabet, using the basic 26-letter Latin alphabet plus the three additional letters Å / å, Ä / ä, and Ö / ö constructed in modern time from the habit of writing the latter letter of aa, ae and oe on top of the former
Edited sentence: The Swedish alphabet is a 29-letter alphabet, using the basic 26-letter Latin alphabet plus the three additional letters Å / å, Ä / ä, and Ö / ö constructed in modern time from the habit of writing the latter letter of "ao", "ae" and "oe" on top of the former