Third, +WDC(T) also outperforms DL4NMT, revealing that it is reasonable and effective to emphasize domain-specific words in model training.. Last, +WDC achieves the best performance when compared with both +WDC(S) and +WDC(T).
we believe that word-level domain contexts on the both sides are complementary to each other, and utilizing them simultaneously is beneficial to multi-domain NMT.