Code-Switching in Lord of the Rings?

There are probably other and better examples, but this one just struck me tonight:

‘Alas!’ said Aragorn. ‘Gandalf the Grey fell into shadow. He remained in Moria and did not escape.’  

At these words all the Elves in the hall cried aloud in grief and amazement. ‘These are evil tidings,’ said Celeborn, ‘the most evil that have been spoken here in long years full of grievous deeds.’ He turned to Haldir. ‘Why has nothing of this been told to me before?’ he asked in the elven-tongue.  

‘We have not spoken to Haldir of our deeds or our purpose,’ said Legolas. ‘At first we were weary and danger was too close behind; and afterwards we almost forgot our grief for a time, as we walked in gladness on the fair paths of Lórien.’  

‘Yet our grief is great and our loss cannot be mended,’ said Frodo. ‘Gandalf was our guide, and he led us through Moria; and when our escape seemed beyond hope he saved us, and he fell.’  (LotR II.7 at 355)

It looks like both Celeborn and Legolas are code-switching in this scene.

Celeborn's comment to Haldir obviously switches from the Common Language to the elven-tongue as this rebuke is an internal matter, an aside not intended for all the visitors.

But of course Legolas understands and responds to defend Haldir -- and Frodo jumps in to offer clarification to Legolas's comment.

However, it's already been established that Frodo is not particularly fluent in the elven-tongue(s).*

So I infer that Legolas has responded in the Common Language; otherwise, Frodo would not be able to jump in as he does.  I think it's clear that Frodo is responding to Legolas's seeming down-playing of their grief ("we almost forgot our grief for a time"), without quite understanding the motivation behind Legolas's words (as he would if he'd understood Celeborn's aside to Haldir).

All citations to: Tolkien, J. R. R. The Lord of the Rings. 50th Anniversary One-Volume Edition, HarperCollinsPublishers, 2005.

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FN*

• cf. "It was singing in the fair elven-tongue, of which Frodo knew only a little, and the others knew nothing." (79 - Exiles, in the Shire)
• cf. "At first the beauty of the melodies and of the interwoven words in elven-tongues, even though he understood them little, held him in a spell, as soon as he began to attend to them." (233 - in Rivendell)
• "...then another clear voice spoke in an elven-tongue. Frodo could understand little of what was said, for the speech that the Silvan folk east of the mountains used among themselves was unlike that of the West. Legolas looked up and answered in the same language." (342)
• "Then he shut off the light again, and spoke words of welcome in his elven-tongue. Frodo spoke haltingly in return. ‘Welcome!’ the Elf then said again in the Common Language, speaking slowly. ‘We seldom use any tongue but our own; for we dwell now in the heart of the forest, and do not willingly have dealings with any other folk....'" (343)