If the Forsaken were sealed away in Shayol Ghul since the Age of Legends, with no contact with the outside world, wouldn’t they be speaking the Old Tongue when they woke back up? How did they learn the Common Tongue?
They still do speak the Old Tongue among themselves, but the first two who were freed, Aginor and Balthamel, had been held very near to the edge of the sealing, the reason they were so visibly affected and twisted while the rest came out whole and healthy, and they were very much aware of what had gone on in the world outside. You might say they had floated in limbo while watching three thousand plus years roll by, with the ability to zoom in. That is probably the only reason they didn’t emerge entirely mad. In truth, those two have a much better understanding of the current world than any of the others because they watched it forming. They don’t have a complete knowledge, because they couldn’t see and hear everything at once, but they have an overview that is unavailable to any of the others, excepting Ishamael to a lesser extent. But then, he’s a special case.
For the rest (aside from Ishamael), who spend those thousands of years in a dreamless sleep, the language spoken “here and now” was derived from the Old Tongue. I’ve heard the analogy used of a well-educated, highly intelligent citizen of ancient Rome needing to learn modern Italian. It would hardly be a slam-dunk, but he or she would have the roots of the language already. In the case of the Forsaken, the task is actually easier than that of the ancient Roman, since modern Italian is a more complex language than Latin, while the Old Tongue, as I have said time and again, is more complex and nuanced than the language of “today.”
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