I. Introduction
With the rapid development of artificial intelligence and machine learning technology, natural language processing (NLP) has become a hot area of research. The goal of NLP is to enable computers to understand and process human language to achieve functions such as automatic translation, sentiment analysis, and intelligent question and answer. The introduction of deep learning has brought revolutionary changes to NLP, especially showing unprecedented capabilities in processing large-scale language data. However, with the increase in tasks and the complexity of data, the traditional single-task learning model has gradually revealed its limitations. Multi-task learning (MTL), as an effective learning strategy, improves learning efficiency and model generalization ability by learning related tasks at the same time [1].