# Levi decomposition for the parabolic subgroups

This question is for the algebraic groups. I find I cannot understand Levi decomposition for the parabolic subgroups well.

Denote the parabolic subgroup is P=LV, L is Levi subgroup. I guess that for the classical group, L is the diagonal element and the left part of it and V is right part of it with all the diagonal elements are 1.

Am I right? If yes, how to show it; if no, please give other interested examples.

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