This is addressed in the original announcement post of SyntaxNet[0]: The major source of errors at this point are examples such as the prepositional phrase att

This is addressed in the original announcement post of SyntaxNet[0]: The major source of errors at this point are examples such as the prepositional phrase attachment ambiguity described above, which require real world knowledge (e.g. that a street is not likely to be located in a car) and deep contextual reasoning. Machine learning (and in particular, neural networks) have made significant progress in resolving these ambiguities. But our work is still cut out for us: we would like to develop methods that can learn world knowledge and enable equal understanding of natural language across all languages and contexts. The SyntaxNet team thinks that this is indeed a major source of errors and seems to be a focus of their work going forward. [0] - http://googleresearch.blogspot.com/2016/05/announcing-syntaxnet-worlds-most.html http://googleresearch.blogspot.com/2016/05/announcing-syntax...