Some exercises...

Here are some lists and exercises that can provide ya'll with moreeeeee plurals! ;D

http://english-zone.com/spelling/plurals.html

http://web2.uvcs.uvic.ca/elc/studyzone/330/grammar/irrplu.htm

http://www.scribd.com/doc/3271143/List-of-100-Irregular-Plural-Nouns-in-English

Remember some,

alumnus	alumni
cactus	cacti
focus	foci/focuses
fungus	fungi/funguses
nucleus	nuclei
radius	radii
stimulus	stimuli

So, many cactus is called cacti!