  We constructed new classes of exact multi-lump solutions of mKP-1,2 equations
with integrable boundary condition $u(x,y,t)\big|_{y=0}=0$ by the use of
$\overline\partial$-dressing method of Zakharov and Manakov. We exactly
satisfied reality and boundary conditions for the field $u(x,y,t)$ using
general determinant formula for multi-lump solutions. We illustrated new
calculated classes by simple examples of two-lump solutions and demonstrated
how fulfilment of integrable boundary condition $u\big|_{y=0}=0$ via special
nonlinear superposition of several single lumps leads to formation of certain
eigenmodes for the field $u(x,y,t)$ in semiplane $y\geq0$, the analogs of
standing waves on the string arising from corresponding boundary conditions at
endpoints of string.
