The numbers in the figure, separated by a slash, indicate how many times each n-gram is generated by each of the two systems.
interestingly, BE → EN does not seem to benefit from pre-training in the multilingual scenario, which hypothesize is due to the fact that: 1) Belarusian and Russian are only partially mutually intelligible (Corbett and Comrie, 2003), i.e., they are not as similar; 2) the Slavic languages have comparatively rich morphology, making sparsity in the trained embeddings a larger problem.