Abstract: This paper firstly introduces a new SFG transitivity paradigm and revisits there be structure in English. It finds that the classical Existential process is a transitivity category, hence semantic; there be pattern is the corresponding grammatical realization, hence a grammatical concept. Then it explores 33 kinds of metaphors in there be construction with reference to construction and conceptual metaphor theory. The results show that all the metaphors involved are produced along the process from semantic systems to ［text］ as meaning, a process of instantiation; they are still within the domain of grammatical metaphors, but agree with the cognitive process of blending and (or) mapping from the source process type to the target process type.