17. A system comprising: one or more computing devices operable to perform operations including: identifying multi-lingual parallel text associating a source language, a target language, and one or more bridge languages; determining a direct alignment between the source language and the target language wherein the direct alignment represents a word-for-word connection between source language and target language words; determining a first bridge-based alignment between the source language and the target language using a first bridge language that is distinct from the source language and the target language, wherein the first bridge-based alignment is determined based in part on a first posterior probability matrix for a first alignment from the source language to the first bridge language and a second posterior probability matrix for a second alignment from the first bridge language to the target language; using the direct alignment between the source language and the target language to generate a first candidate translation of an input text in the source language to the target language; using the first bridge-based alignment to generate a second candidate translation of the input text in the source language to the target language; and determining a consensus translation using the candidate translations.
17. A system comprising: one or more computing devices operable to perform operations including: identifying multi-lingual parallel text associating a source language, a target language, and one or more bridge languages; determining a direct alignment between the source language and the target language wherein the direct alignment represents a word-for-word connection between source language and target language words; determining a first bridge-based alignment between the source language and the target language using a first bridge language that is distinct from the source language and the target language, wherein the first bridge-based alignment is determined based in part on a first posterior probability matrix for a first alignment from the source language to the first bridge language and a second posterior probability matrix for a second alignment from the first bridge language to the target language; using the direct alignment between the source language and the target language to generate a first candidate translation of an input text in the source language to the target language; using the first bridge-based alignment to generate a second candidate translation of the input text in the source language to the target language; and determining a consensus translation using the candidate translations. 23. The system of claim 17 , where determining a consensus translation using the candidate translations includes evaluating a score for each candidate translation.