Even Lines

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

namespace EvenLines
{
    public class EvenLines
    {
        static void Main()
        {
            string inputFilePath = @"text.txt";

            Console.WriteLine(ProcessLines(inputFilePath));
        }

        public static string ProcessLines(string inputFilePath)
        {
            using StreamReader reader = new StreamReader(inputFilePath);
            char[] symbolArray = new char[] { '-', ',', '.', '!', '?' };
            int counter = 0;
            string line = reader.ReadLine();
            StringBuilder sb = new StringBuilder();

            while (line != null)
            {
                if (counter % 2 == 0)
                {
                    foreach (char symbol in symbolArray)
                    {
                        if (line.Contains(symbol))
                        {
                            line = line.Replace(symbol, '@');
                        }
                    }
                    string newLine = line.Split().Reverse().ToString();
                    sb.AppendLine(newLine);
                }
                counter++;
                line = reader.ReadLine();
            }
            return sb.ToString().Trim();

        }

    }
}