Being from southern-central Canada...
Mary and
Merry are the same for me.
Kerry/Kerry/Keri and Carrie/Karrie are the same.
Kari is CAR-ee for me too.
I say
Alice and
Alyce the same.
Joanna is Jo-ANN-ah and
Johanna is Jo-HAHN-ah.
Madelyn is mad-ah-lyn.
Madeline is mad-ah-line/mad-ah-lyn, depending on how I'm feeling (usally mad-ah-line...my mom actually didn't want to call me
Madeline because she thought people would pronounce it as mad-ah-lyn).
Madeleine is mad-ah-len and
Madelaine is mad-ah-lain.
Ariel is AIR-ee-ul and
Arielle is air-REE-ell, with a rolling r.