We construct mass deformed SU(N) L-BLG theory together with $U(M-N)_k$ Chern-Simons theory. This mass deformed L-BLG theory is a low energy world volume theory of a stack of $N$ number of M2-brane far away from $C^4/Z_k$ singularity. We carry out thi
s by defining a special scaling limit of the fields of this theory and simultaneously sending the Chern-Simons level to infinity.
We study the Wilson loops and defects in the three dimensional QFT from the D-branes in the AdS(4) x CP**3 geometry. We find out explicit D-brane configurations in the bulk which correspond to both straight and circular Wilson lines extended to the b
oundary of AdS(4). We analyze critically the role of boundary contributions to the D2-branes with various topology and to the fundamental string actions.
We study the solutions for fundamental string rotating in a background generated by a 1+1 dimensional intersection of two orthogonal stacks of fivebranes in type IIB string theory. We show the existence of magnon like solutions for the string moving
simultaneously in the two spheres in this background and find the relevant dispersion relation among the various conserved charges.
