c# – Asp.Net MVC我的代码出了什么问题？

public List<string> getWords(int wrNum)
{
    IDVLTest d3 = new DVLTest();
    for (int i = 0; i < wrNum;i++ )
    {
        string word = d3.getRandomWord().Text;
        Words.Add(new WordView { Word = word,Status = WordStatus.Right });
    }
    return Words.Select(w=>w.Word).ToList();
}

public class DVLTest:IDVLTest
{
...
    public Word getRandomWord()
    {
        Random r = new Random();
        int i = r.Next(DVL_Entitie.Words.Count());
        return DVL_Entitie.Words.ToList().ElementAt(i);
    }
...
}