tones again, some hard evidence

[djwebb2004]

The answer to the questioni about the importance of tones is this: you can get away with a certain percentage of vague/wrong tones, particularly in the right context, or if you are saying things in an idiomatic way, but some individual words will interrupt the flow of conversation if not said right. I find that saying "Diet Coke" in Chinese suddenly produces a problem - it should be jiànyí kělè, but for some reason the fourth tone jian doesn't sound fourthy enough, and so the phrase is ruined. You can be understood with 80% of tones right - after all tonal production varies from city to city in China anyway - but especially for anything unusual, or anything that could be ambiguous you need to get the tones right.