Really appreciate for your response. If I understand correctly, actually, you provide two ways: 1. use the teacher forcing for the validation 2. add the “metirc of interest” during validation without teacher forcing. I also wonder that should I control the teacher forcing ratio (some timestamps, use the teacher forcing, some timestamps, use the generated word)? In such case, the model may have better generalization ability.  Also, how to handle the dropout/batch normalization in validation phase? Use it or not? Thanks!