“…There are many specific sentiment tasks, and these tasks usually depend on different types of sentiment knowledge including sentiment words, word polarity and aspect-sentiment pairs. The importance of these knowledge has been verified by tasks at different level, for instance, sentence-level sentiment classification (Taboada et al, 2011;Shin et al, 2017;Lei et al, 2018), aspect-level sentiment classification (Vo and Zhang, 2015;Zeng et al, 2019), opinion extraction (Li and Lam, 2017;Gui et al, 2017;Fan et al, 2019) and so on. Therefore, we assume that, by integrating these knowledge into the pre-training process, the learned representation would be more sentimentspecific and appropriate for sentiment analysis.…”