For a noncollocated mass-dashpot-spring system with $B=CTΓ$, a novel approach is proposed to gain a better insight into the fact that none of its transmission zeros lie in the open right-half of the complex plane. In addition, the transmission zeros have physical meanings and will simply be the natural frequencies of a substructure constrained in the equivalently transformed system. Moreover, it is also shown that transmission zeros interlace with poles along the imaginary axis for a mass-spring system with $B=CTΓ$. They also interlace with poles along the negative real axis for a mass-dashpot system with $B=CTΓ$. Finally, two examples are used to illustrate the interlacing property.

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