  The $T_N$ theory is a non-Lagrangian theory with SU(N) flavor symmetry. We
argue that when mass terms are given so that two of SU(N)'s are both broken to
SU(N-1) x U(1), it becomes $T_{N-1}$ theory coupled to an SU(N-1) vector
multiplet together with N fundamentals. This implies that when two of SU(N)'s
are both broken to U(1)$^{N-1}$, the theory becomes a linear quiver.
  We perform various checks of this statement, by using the 5d partition
function, the structure of the coupling constants, the Higgs branch, and the
Seiberg-Witten curve. We also study the case with more general punctures.
