(* A small extension of the code by belisarius in *)
(* http://stackoverflow.com/questions/6797651/plotting-a-number-line-in-mathematica/6797911#6797911 *)

intPlot[ss_, {s_, e_}, ee_] := intPlot[{{ss, {s, e}, ee}}]
intPlot[ints : {{_String, {_?NumericQ, _?NumericQ}, _String}..}] := 
 With[{min = Min[ints[[All, 2, 1]]], max = Max[ints[[All, 2, 2]]]}, 
  Graphics[Table[
    With[{ss = int[[1]], s = int[[2, 1]], e = int[[2, 2]], ee = int[[3]]},
     {Red, Thickness[.01], Text[Style[ss, Large, Red, Bold], {s, 0}], 
      Text[Style[ee, Large, Red, Bold], {e, 0}], 
      Line[{{s, 0}, {e, 0}}]}], {int, ints}], 
   Axes -> {True, False}, AxesStyle -> Directive[Thin, Blue, 12], 
   PlotRange -> {{min - .2 Abs@(min - max), max + .2 Abs@(min - max)}, {0, 0}}, 
   AspectRatio -> .1]]

(* Examples *)

intPlot["[", {3, 4}, ")"]
intPlot[{{"(", {1, 2}, ")"}, {"[", {3, 4}, ")"}}]