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Connecting three zigzag graphene nanoribbons (ZGNRs) together through the sp3 hybrid bonds forms a star-like ZGNR (S-ZGNR).Its band structure shows that there are four edge states at k =0.5,in which the three electrons distribute at three outside edge sites,and the last electron is shared equally (50%) by two sites near the central site.The lowest conductance step in the valley is 2,two times higher than that of monolayer ZGNR (M-ZGNR).Furthermore,in one quasithree-dimensional hexagonal lattice built,both of the Dirac points and the zero-energy states appear in the band structure along the z-axis for the fixed zero k-point in the x-y plane.In addition,it is an insulator in the x-y plane due to band gap 4 eV,however,for any k-point in the x-y plane the zero-energy states always exist at kz =0.5.