Automatically creating word breakers which segment words into morphemes is described, for example, to improve information retrieval, machine translation or speech systems. In embodiments a cross-lingual phrase table, comprising source language (such as Turkish) phrases and potential translations in a target language (such as English) with associated probabilities, is available. In various examples, blocks of source language phrases from the phrase table are created which have similar target language translations. In various examples, inference using the target language translations in a block enables stem and affix combinations to be found for source language words without the need for input from human-judges or prior knowledge of source language linguistic rules or a source language lexicon.