We will consider the first two levels of affixation because they differ significantly. Here is a table that compares affixation on Levels 1 and 2:
-ate, -ion, -ity, -ic, sub-, de-, in-
Affixation causes stress shift:
Trisyllabic shortening occurs:
Nasal assimilation occurs:
in + legal -> illegal
Affixes may attach to stems:
Affixation is less productive and more exception ridden.
-ly, -ful, -some, -ness, re-, un-, non-
Affixation does not affect stress:
No trisyllabic shortening occurs:
Nasal assimilation is blocked:
un + ladylike -> unladylike, not *ulladylike
Affixes attach only to words:re-open, de-regulate
Affixation is more productive and less exception ridden.