Even when the POS of a word can be determined with certainty by only the word on the left, for example, the neuro tagger still tries to tag based on the complete context.
in general, what the neuro tagger can easily acquire by learning is the rules whose conditional parts are constructed by all inputs ipt x (x = t 0 l;1 11 ; t + r) that are joined with an AND logical operator, i.e., (ipt t0l & 1 11ipt t & 1 1 1ipt t+r !