I am taking a class via my employer about business grammar right now. We are using The Gregg Reference Manual . I am actually enjoying it.
And I write very well (not good).
re: the use of " 's" to pluralize words. (b/c that irks the HELL out of me)
Our book actually has examples when this is ok, usually for clarity's sake.
EX: (p. 182)
dotting the i's
four c.o.d's
sending out three bcc's
But NOT "the Zeta's, Sigma's and AKA's are all probating tomorrow".