string myString = "1.In order to get a Disneyland ticket
2.that includes the new Star Wars land
3.you must stay at a Disney hotel
4.the night of or night before your visit.
5.Day passes without a hotel
6.reservation will be available after June 23";

public static void Main(string[] args)
    {
        int vowelCount = 2; // match words with 2 or more vowels
        int skipWord = 3; // Consider every 3rd word only
        int skipLine = 2; // Consider every 2nd line only
        int wordCount = 0;
        int lineCount = 0;

        string myString = @"1.In order to get a Disneyland ticket
2.that includes the new Star Wars land
3.you must stay at a Disney hotel
4.the night of or night before your visit.
5.Day passes without a hotel
6.reservation will be available after June 23";";

        List<string> myList = myString.Split(Environment.NewLine).ToList();
        List<string> lineWords = new List<string>();
        char[] vowels = {'a', 'e', 'i', 'o', 'u'};

        for (int i = skipLine; i <= myList.Count; i += skipLine)
        {
            int origWordCount = wordCount;
            lineWords = myList[i - 1].Split(' ').ToList();
            for (int j = skipWord; j <= lineWords.Count; j += skipWord)
            {
                char[] wordArr = lineWords[j-1].ToLower().ToCharArray();
                int match = vowels.Intersect(wordArr).Count();
                if (match >= vowelCount)
                    wordCount++;
            }
            if (wordCount > origWordCount)
                lineCount++;
        }

        Console.WriteLine("WordCount : {0}, LineCount : {1}", wordCount, lineCount);