Text normalization for a TTS (continued)
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The same as in E05 plus:

- convert numbers 0-999999 into words
- convert "&" into "and"
- convert "+" into "plus
- converting "-", "*", "/" into "minu", "times", "divided by" when with numbers,
  "hyphen", "star", "slash" otherwise

POINTS: 4
DEADLINE: 2020-01-28 23:59