Recently it has been speculated that the Ward identities associated with the string dualities and the gauge symmetries can be used as guiding principles to find all components of the scattering amplitude of n supergravitons from a given component of the S-matrix. In this paper, we apply the Ward identities associated with the T-duality and the gauge symmetries on the disk-level S-matrix element of one RR (p-3)-form, one NSNS and one NS states, to find the corresponding S-matrix elements of the

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... R (p-1)-form, (p+1)-form or the RR(p+3)-form on the world volume of a D_p-brane. Moreover, we apply these Ward identities on the S-matrix element of one RR (p-3)-form and two NSNS states to find the corresponding S-matrix elements of the RR (p-1)-form, (p+1)-form, (p+3)-form or the RR (p+5)-form.