There are tons of phrases and expressions in Chinese that follow the ...不... pattern, such as 受不了， 放不下， 來不及, etc.

I've noticed that in Skritter, some of the 不 characters in these phrases are saved as neutral tone, some are saved as 4th tone, and I think that even some are saved as 2nd tone because of the 不tone change.

In short, it's inconsistant. I like the way Taiwanese people pronounce tones (only tones) , because they're very consistant, whereas northern Chinese ppl have all sorts of neutral tone exceptions that make things far more complicated and inconsitant.

I personally think that the 不 character in these phrases should never be saved as neutral. What does everyone think?

Yes, this is a problem not only in the "v+不了" structure but in all phrases containing the character 不。 Linguists seem to have different viewpoints on whether or not pinyin should adjust for tone changes. In any event, Skritter should be consistent with this.

another thing that is inconvenient about this is, when we come across expressions like 受不了 in our queues and put in 4th tone for 不, it marks it as wrong and we have to keep doing it over and over

我受不了！

The Skritter guys do try to make sure that Skritter reflects the true pronunciation, although "the true pronunciation" is unfortunately sometimes not well defined due to regional variations.

I'm curious about the examples you gave. Maybe some people more expert than me can help clear this up:

受不了 - nciku, MDBG, and Yellowbridge all say 不 is fourth tone.
放不下 - couldn't find it in nciku; MDBG says 不 is neutral, while Yellowbridge says it's fourth tone.
來不及 - nciku and MDBG say 不 is neutral, Yellowbridge says it's fourth tone.

As far as tone sandhi (changes in 一 and 不 based on the following tone), whenever I find what I think is an error I send it in via the feedback form. The Skritter guys usually respond via email very quickly.

James

@ Bohan- Sorry but I entirely disagree. Don't you have a Taiwanese girlfriend? Also, aren't you learning in the states? I am leading up to something, so please take no offense to what I say next. You are biased for the Taiwanese pronunciation.

I was trained in the north of the mainland. I prefer the Shandong (山东） or Dalian （大连） pronunciations. A while back some people on this forum were championing the Taiwanese pronunciation. Someone said, "with the exception of the s/sh, z/zh problems their Mandarin is very good." That is a HUGE deal to me. If you want to pick an isolated place to study, I say the best in the entire world is 大连.

The neutral tones seem fairly consistent on the mainland. This is a problem with entries in the system, not the way people speak.

I admit I am biased towards the north, though. Lets pick on my favorite area a moment to be fair.

The north has... the r/儿. First of all, once you get out of Beijing, many of the Rs people use are actually correct. Many southerners say they aren't, but they are actually wrong. Why do I say this? I had some bad experiences with southern Chinese trying to correct Rs that were correct, so I went to my linguist Mandarin teacher, her masters was in Linguistics and not teaching, and had her research the absolute rules of it. There are three rules and a hand full of exceptions where the R is 100% legal. I asked her to give me sources. She couldn't just say it was that way. That is like saying, "Mommy said I can!" Before she was done, she had grad-school textbooks out on our table. I also learned there are a few exceptions that are acknowledged as legal even though they follow none of the rules. For example, 点儿 is legal IN AN INFORMAL SITUATION. That is why you never see it on CCTV. That is a more formal setting.

I put a qualifier at the start, but remember I said I was picking on the north? A TON of the Rs in Beijing and even to a lesser extent outside of Beijing are illegal. My personal favorite illegal R is 饭馆儿. It seems like in Beijing every other dang word has a R attached to it. That certainly isn't proper Mandarin. I try to make my R usage fairly legal, but I do have the 北方味儿。

The point I am getting at is simply this. Chinese have to live with each others' eccentric pronunciations. Since we are all studying Chinese, sadly, we have now also undertaken that burden.

Sorry Bohan, but you might as well just get used to it. Every time I hear a Chinese chef say on TV cao3mian4, I force myself to just suck it up and accept the wonderful eccentricities of Mandarin. Give me another couple of years and hopefully my biase will be gone and I can just enjoy the language, regardless of whomever is speaking it.

My limited understanding is that (in the north at least) 不 should be neutral in all of those, and I'm not sure about when the third character in a potential complement like that is also neutral. I'm not sure where to turn for maximum authority on them, though.

It's possible that we would try to support either neutral or full tone on both 不 and common potential complement characters, if it was standard elsewhere to not use neutrals, but thus far I've been aiming to prevent full tones on them so as to instruct that they should be neutral.

In a dream world we could select which regional variant we wanted and then have the tones (including the audio!) match that region's standard. Until then, how about being able to have custom tones, much like the custom definitions. Perhaps this crowd-sourcing could be used to populate the regional variation profile data. It would also be good to be able to (manually) tell Skritter to stop playing the audio for certain words where the ChinesePod pronunciation doesn't match the pronunciation I want to learn (eg 頭髮 tou2 fa3).

Ah,the option to have skritter not play the audio for certain words is a good idea. I know nothing about programming, but that doesn't seem too difficult.

I'd be wary of turning off the sound for some words as a new feature. It would add complication (another option box to enable the feature, some way for each word to modify it, user interface changes to accommodate same, database changes to record it). I might be wrong but I don't think it would be a widely used feature either. If you had a plug-in or firewall that would let you block certain files that should work (if you block the file from loading, Skritter won't play it) and might be an acceptable work-around.

Ideally we'd have several different sound sources that would get chosen randomly but that would require a lot more recordings. If you are learning Chinese to communicate then it's useful to be exposed to various correct pronunciations (and some regional ones that aren't "correct" in standard Mandarin but are nevertheless what is spoken). I get to Beijing a fair bit and am always trying to wrap my head around some of the slang there. My teacher (not from Beijing) had to look up some phrases when I was studying from a particular Beijing-Chinese textbook (my in-laws all speak with Beijing accents so I want to learn the slang too).

I would love to have different pronounciations for various words, like randomly.