  We Microsoft Research Asia made submissions to 11 language directions in the
WMT19 news translation tasks. We won the first place for 8 of the 11 directions
and the second place for the other three. Our basic systems are built on
Transformer, back translation and knowledge distillation. We integrate several
of our rececent techniques to enhance the baseline systems: multi-agent dual
learning (MADL), masked sequence-to-sequence pre-training (MASS), neural
architecture optimization (NAO), and soft contextual data augmentation (SCA).
