Here are some rules for Latin/Greek plurals:
If the singular ends in
um, drop the
um and add an
a. For example datum --> data.
If the singular ends in
on, drop the
on and add an
a. For example ganglion --> ganglia.
If the singular ends in
a, add an
e. For example ampulla --> ampullae.
PLURAL-izing by Karen Gertz (For medical terms. Includes list of exceptions and an exercise.)
Plurals of Latin/Greek Words (General rules.)
Use those rules to come up with your own answers, then post them here and we'll correct them if necessary.