On the base point free theorem for KLT threefolds in large characteristic

In this article we present a refinement of the base point free theorem for threefolds in positive characteristic. If $L$ is nef Cartier divisor numerical dimension at least one on projective Kawamata log terminal threefold $(X,\Delta)$ over perfect field $k$ characteristic $p \gg 0$ such that $L-(K_X+\Delta)$ big and nef, then show linear system $|mL|$ all sufficiently large integer $m>0$.