I was just curious to see if the machine would accept Vietnamese2020 and output the correct pronunciation. I was stunned! The result was 99%!!!

The test engine: The Online Text to Speech Engine @ https://inforobo.com/text-to-speech-online/

The text to be tested: The first 3 paragraphs of the article "Vấnnạn Liênhoàn" @ http://vny2k.com/vny2k/VannanLienhoan.htm
The words with (only slightly) less than perfect pronunciation: nhậnthứcrõrệt, hiệnhữu, vấnnạnliênhoàn

Error metrics provided by https://wordcounter.net/: 3 out of 309 words OR 36 out of 2,062 characters

VERY IMPRESSIVE.

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