▎ 摘　　要

We introduce a minimum tight-binding model with only three parameters extracted from graphene and untwisted bilayer graphene. This model reproduces quantitatively the electronic structure of not only these two systems and bulk graphite near the Fermi level, but also that of twisted bilayer graphene including the value of the first magic angle, at which bands at E-F flatten without overlap and two gaps open, one above and one below E-F. Our approach also predicts the second and third magic angle. The Hamiltonian is sufficiently transparent and flexible to be adopted to other twisted layered systems.