Subword units like character (Vilar et al., 2007;Tiedemann, 2009), orthographic syllables (Kunchukuttan and Bhattacharyya, 2016b) and byte pair encoded units (Kunchukuttan and Bhattacharyya, 2017) have been used with varying degrees of success.
if no parallel corpus is available between two languages, pivot-based SMT (Gispert and Marino, 2006;Utiyama and Isahara, 2007) provides a systematic way of using an intermediate language, called the pivot language, to build the source-target translation system.