  By using the so-called matrix-product ground state approach, a few
one-dimensional quantum systems, including a frustrated spin-1/2 Heisenberg
ladder, the ferromagnetic t-J-V model at half-filling, the antiferromagnetic
$J_z-V$ at 2/3 filling and the antiferromagnetic $t-J_z-V$ model at
half-filling, are solved exactly. The correlation functions in the ground
states are calculated respectively. Some relevant results are also discussed.
