As most Star Trek fans know, Klingon is now a spoken language. Are the Middle-earth languages spoken in the LOTR/Hobbit films faithfully pronounced from the texts written by Tolkien? To clarify, when Gandalf speaks in a tongue other than English, is the actor reciting the language the same way J.R.R. Tolkien would have when he was creating it when he was writing the epic tales so that a Tolkien scholar would be able to understand what Sir Ian McKellen is actually saying?
Insofar as it was possible to do so, yes. Linguist David Salo was hired to develop Tolkien's languages into forms usable for the movie. He wrote this in a message to a mailing list devoted to those languages:
Part of my intention, my particular vision and contribution to this movie, was to create sentences which would be intelligible to the people who study the languages (...) I'm enormously happy to see some people saying based on their knowledge of Elvish, great or small, that they recognized and understood some of what they heard on the screen.
In practice, what this means is:
- Tolkien's writings include fairly complete versions of Sindarin and Quenya (the two Elvish languages), but some extra vocabulary was invented as needed.
- Tolkien only gives brief snippets of Khudzûl (Dwarvish) and the Black Speech, which were greatly expanded (mostly for use in the soundtracks).
- The language of the Rohirrim was represented by Old English, reflecting the fact that it relates to the language of the hobbits in the same way that Old English relates to modern English. This is consistent with the way it was depicted in the books.
More details can be found here.