Reduplication
In its original form GR used the two "spare" letters of the alphabet, v and x, to indicate reduplication. This mimicked the method by which the Chinese script indicates repeated characters with an iteration mark (々). In GR the letter x indicates that the preceding syllable is repeated (shieh.x = shieh.shieh, "thank you"), vx being used when the preceding two syllables are repeated (haoshuo vx! = haoshuo haoshuo! "you're too kind!").
This concise but completely unphonetic, and hence unintuitive, device appears in Chao's Mandarin Primer and all W. Simon's texts (including his Chinese-English Dictionary). Eventually, however, it was silently discarded even by its inventor: in Chao's Grammar as well as his Sayable Chinese all reduplicated syllables are written out in full in their GR transcription.
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