Every planar graph without adjacent short cycles is 3-colorable

Two cycles are {\em adjacent} if they have an edge in common. Suppose that $G$ is a planar graph, for any two adjacent cycles $C_1$ and $C_2$, we have $\mathrm{\mid }{C}_1\mathrm{\mid }+\mathrm{\mid }{C}_2\mathrm{\mid }\ge 11$, in particular, when $\mathrm{\mid }{C}_1\mathrm{\mid }=5$, $|C_{2}| \geq 7$\mathrm{.}Weshowthatthegraph$G$ is 3-colorable.