Abstract: This paper has double functions, one of which is to present to Chinese linguists and applied linguists in China the semantic system network for MOOD in English that has been developed in the framework of the Cardiff Grammar, and the other of which is to explain the reason why we intend to replace the earlier MOOD system by the present one. The first four sections are intended to fulfil the second purpose by specifying the orientation of the study, answering three questions concerning the MOOD system, reviewing other attempts to draw system networks for the semantics of MOOD, and suggesting a number of factors that may have inhibited the semanticizing process of the earlier MOOD system network. The fifth section is intended to fulfil the first purpose of the paper, together with the appendices, where the semanticized MOOD system network is presented.