“…In [11], we gave a complete classification of finite irreducible conformal modules of W(a, b), T SV (a, b) and T SV (c). In [12,13,19], Ling and Yuan classified all extensions of finite irreducible conformal modules over W(1, 0) , W(1 − b, 0) and T SV ( 3 2 , 0). In this paper, we deal with the same problem for W(a, b), T SV (a, b) and T SV (c).…”