I was fed up, so here it is in c#

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace CodeChallenge
{
class Program
{
private static List<string> wordsToRemove = new List<string>() { "dog", "cat" };

static void Main(string\[\] args)
{
  string text = "dog cat monkey dog horse dog";

  string\[\] words = text.Split(' ');
  string\[\] output;
  int start = 0;
  int end = 0;

  // test the start
  if (wordsToRemove.Contains(words\[0\]) && words.Length > 0)
    start = 1;

  // test the end
  if (wordsToRemove.Contains(words\[words.Length - 1\]) && words.Length != start)
    end = (words.Length - 1) - start;
  else
    end = words.Length - start;

  //build
  output = new string\[end\];
  Array.Copy(words, start, output, 0, end);

  //output
  Console.WriteLine(string.Join(" ",output));
}

}
}