Two papers accepted to the ACL-IJCNLP 2021 main conference, and two papers accepted to the Findings of ACL. Congratulations to Xuebo Liu, Runzhe Zhan, and all co-authors. Check out the papers on Reducing Copying Errors in Pre-Training for Neural Machine Translation, Difficulty-Aware Machine Translation Evaluation, Rejuvenating Low-Frequency Words: Making the Most of Parallel Data in Non-Autoregressive Translation, and Progressive Multi-Granularity Training for Non-Autoregressive Translation.