Semantics processing is a fundamental research domain in computational linguistics. In the era of LLMs, the advancement of research in this domain appears to be decelerating. However, the study of semantics is multi-dimensional in linguistics. The research depth and breadth of semantics processing can be largely improved with new technologies. In this chapter, we analyze five semantic processing tasks: WSD, NER, concept extraction, anaphora resolution, and subjectivity detection.We survey theoretical research in these fields, advanced methods, and downstream applications, with the hope of encouraging scholars to focus on these fine-grained NLU tasks. The review of theoretical research may also inspire new tasks and technologies in this domain. Finally, we compare different semantic processing techniques and summarize their technical trends, application trends, and future directions.