  In this paper, we mainly consider the initial boundary problem for a
quasilinear parabolic equation \[ u_t-\mathrm{div}\left(|\nabla u|^{p-2}\nabla
u\right)=-|u|^{\beta-1}u+\alpha|u|^{q-2}u, \] where $p>1,\beta>0$, $q\geq1$ and
$\alpha>0$. By using Gagliardo-Nirenberg type inequality, energy method and
comparison principle, the phenomena of blowup and extinction are classified
completely in the different ranges of reaction exponents.
