The 12 non-degenerate phonon vibrational modes at the center of Brillouin zone for a series of single-wall carbon nanotubes have been analysed in a previous paper.［1］ The E1 and E2 of degenerate phonon vibrational modes are further discussed in this paper and the relations between frequency-chirality and frequency-tube diameter for E1 and E2 vibrational modes are also demonstrated.