First of all, the discrimination of degree of freedom and structural system is the basis, which should be the first step to judge whether a structure is established. For geometrically invariant systems, structural mechanics analysis is not needed. Then the mechanical analysis part. It can be divided into computational structural mechanics and conceptual structural mechanics. The former is the basis of the latter. As for the latter, personally, mastering conceptual structural mechanics is the ultimate goal of our study of structural mechanics, and it is also one of the basic qualities we should have in structural design. Computational mechanics generally includes (statically determinate structural analysis), truss analysis, force method, displacement method (matrix displacement method), moment distribution method and shear distribution method, which follow the arrangement order from shallow to deep and from general to special. There should be no doubt that statically determinate structure analysis and truss analysis are the simplest structural mechanics analysis contents; Force method is aimed at the structure with less static indefinite times; Displacement method is aimed at the structure with high static indefinite times; Matrix displacement method is born out of displacement method, which is more general, suitable for all structures including statically indeterminate structures, and is the theoretical basis of structural computers. Moment distribution method and shear distribution method are simplified calculation methods for special structures. The arch is not mentioned separately above, because the arch is a kind of seemingly special statically indeterminate structure or statically indeterminate structure with less times of statically indeterminate, which cannot be separated from the framework of statically indeterminate structure analysis and force method.