Subgraph

Subgraph[g,{v1,v2,…}] gives the subgraph of the graph g generated by the vertices vi.

Subgraph[g,{e1,e2,…}] gives the subgraph generated by the edges ej.

Subgraph[g,patt] gives the subgraph generated by the vertices and edges that match the pattern patt.

Subgraph[{v->w,…},…] uses rules v->w to specify the graph g. 

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