The Hamiltonian of an N -boson system confined on a ring with zero spin and repulsive interaction is diagonalized. The excitation of a pair of p -wave particles rotating reversely appears to be a basic mode. The fluctuation of many of these excited pairs provides a mechanism of oscillation; the states can be thereby classified as oscillation bands. The particle correlation is studied intuitively via the two-body densities. Bose clustering originating from the symmetrization of wave functions is found, which leads to the appearance of one-, two-, and three-cluster structures. The motion is divided into being collective and relative; this leads to the establishment of a relation between the very high vortex states and the low-lying states.