system that by default does not incorporate any linguistic information (e.g., syntax or morphology or transliteration knowledge). As a result, words that were not directly observed in the bilingual training data were untranslatable. Names, in particular, are problematic. For example, the lack of translation for [*Nagaland*]{} and [*Nagas*]{} induces multiple omissions throughout the translated text, thus producing several instances where the [*holder*]{} of a claim (or [ *belief*]{}) is missing. This is because out of vocabulary words are deleted from the Moses output.

![The evolution of a semantically informed approach to our synchronous context free grammars (SCFGs). At the start of summer the decoder used translation rules with a single generic non-terminal symbol, later syntactic categories were used, and by the end of the summer the translation rules included semantic elements such as modalities and negation, as well as named entities.[]{data-label="Evolution-to-SIMT-Joshua"}](graphics/Evolution-to-SIMT-Joshua.pdf){height="3in"}

We use syntactic and semantic tags as higher-order symbols inside the translation rules used by the translation models. Generic symbols in translation rules (i.e., the non-terminal symbol “X”) were replaced with structured information at multiple levels of abstraction, using a tree-grafting approach that we describe below. Figure \[Evolution-to-SIMT-Joshua\] illustrates the evolution of the translation rules that we used, first 