" ACL - Accelerated Contact Linguistics - was, Scile told me, a speciality crossbred from pedagogics, receptivity, programming and cryptography. It was used by the scholar-explorers of Bremen's pioneer ships to effect very fast communication with indigenes they encountered or which encountered them.
In the logs of those early journeys, the excitement of the ACLers is moving. On continents, on worlds vivid and drab, they record first moments of understanding with menageries of exots. Tactile languages, bioluminescent words, all varieties of sounds that organisms can make. Dialects comprehensible only as palimpsests of references to everything already said, or in which adjectives are rude and verbs unholy. I've seen the trid diary of an ACLer barricaded in his cabin, whose vessel has been boarded by what we didn't then know as Corscans - it was first contact. He's afraid, as he should be, of the huge things battering at his door, but he's recording his excitement at having just understood the tonal structures of their speech.
When the ACLers and the crews came to Arieka, there started more than 250 kilohours of bewilderment. It wasn't that the Host language is particularly difficult to understand, or changeable, or excessively various. There were startlingly few Hosts or Arieka, scattered around the one city, and all spoke the same language. With the linguists' earware and drives it wasn't hard to amass a database of sound-words (the newcomers thought of them as words, though where they divided one from the next the Ariekei might not recognize fissures). The scholars made pretty quick sense of syntax. Like all exot languages it had its share of astonishments. But there was nothing so alien that trumped the ACLers or their machines.
The Hosts were patient, seemed intrigued by and, insofar as anyone could tell through their polite opacity, welcoming to their guests. They had no access to immer, nor exotic drives or even sublux engines; they never left their atmosphere, but they were otherwise advanced. They manipulated life with astounding finesse, and they seemed unsurprised that there was sentience elsewhere.
The Hosts did not learn out Anglo-Ubiq. Did not seem to try. But within a few thousand hours, Terre linguists could understand much of what the Hosts said, and synthesised responses and questions in the one Ariekene language. The phonetic structure of the sentences they had their machines speak - the tonal shifts, the vowels and the rhythm of consonants - were precise, accurate to the very limits of testing.
The Hosts listened, and did not understand a single sound. "
― China Miéville , Embassytown