spelling

[jack]

Thanks.

What about this:
1. Ironing (correct)
2. Ironning (Incorrect? Why doesn't it follow that rule?)

[Casiopea]

Thanks.

What about this:
1. Ironing (correct)
2. Ironning (Incorrect? Why doesn't it follow that rule?)

It has to do with its pronunciation:

iron, eye'ern
ironing, eye'er'ning

Both r and n are sonorants, so when -ing is added to iron, n is moved from syllable-final position to syllable-initial position:

rn => r'ning

All the best, :D