Dr Zhai reckons that 100 patterns cover about 40% of the words most people write.

BBC: The software is based on pattern recognition

Both are active in the business: Liu is chairman, Zhai is the president.

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"Eventually you reach a high performance level as each time you trace a word, the pattern will start to be remembered, " said Dr Zhai.

BBC: The software is based on pattern recognition

Zhai, 48, has attended Tulane University.

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