  A nonlinear SO(8) invariant BF type Lagrangian for describing the dynamics of
N M2-branes in flat spacetime has been proposed recently in the literature
which is an extension of the non-abelian DBI action of N D2-branes. This action
includes only terms with even number of the totally antisymmetric tensor
M^{IJK}. We argue that the action should contain terms with odd number of
M^{IJL} as well. We modify the action to include them.
