He has a full linguistic explanation there.
and if you want lessons on how he devised the various dialects of Orcish languages, he has various blog posts on that too.
for the non Tolkien geeks, Salo is a linguist who had an interest in Tolkien's languages, so we tapped to devise non English dialect for the LOTR trilogy.
No, I have no background in linguistics per se, but know enough about Tagalog and ChiShona to know a little about it (and a tiny bit of Navajo, with it's many many irregular verbs and glottal stops).
One of these days, I'll study Chinese to fill in the final gap.