根据微软单词词典生成单词列表 - 在某些时候停止工作 - 为什么？

Question

我编写了一个小应用程序，它生成单词，然后根据 Microsoft Word 2007 词典验证它们。

当我针对 3 个字母长度的英语词典（我猜还有更多字母）对其进行测试时，这对我来说非常有用，但由于某种原因，当我尝试针对希伯来语词典运行它时，它停止工作。

有谁知道为什么吗？如果是，我该如何解决？ 如果有更好的方法来做到这一点，如果有人能指出，我会很高兴。

谢谢。

更新：当我说它停止时，我的意思是它停止检查单词。我得到所有单词组合直到最后，但它们没有被检查。

MainWindow.xaml

<Window x:Class="AllHebrewWords.CreateDictionary"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    Title="List of words" Height="250" Width="150" Closing="Window_Closing" ResizeMode="CanMinimize">
    <Grid>
        <ListBox Margin="10,10,10,10" Name="WordsList" />
    </Grid>
</Window>

MainWindow.xaml.cs

using System.Diagnostics;
using System.Reflection;
using System.Threading;
using Microsoft.Office.Interop.Word;

namespace AllHebrewWords
{
    public partial class CreateDictionary : System.Windows.Window
    {
        private Application app = null;
        private _Document doc = null;
        private Thread thread = null;
        object oMissing = Missing.Value;

        public CreateDictionary()
        {
            InitializeComponent();

            app = new Application();
            object visible = false;
            doc = app.Documents.Add(ref oMissing, ref oMissing, ref oMissing, ref visible);

            thread = new Thread(SearchThread);
            thread.Start();
        } // End of function

        public void SearchThread()
        {
            Stopwatch stopwatch = new Stopwatch();
            stopwatch.Start();
            for (char ch = 'א'; ch <= 'ת'; ch++)
            {
                AddLetter(ch.ToString());
            } // End of for

            object FileName = "C:/Words";
            object FileFormat = WdSaveFormat.wdFormatText;
            doc.SaveAs( ref FileName, ref FileFormat, ref oMissing, ref oMissing,
                        ref oMissing, ref oMissing, ref oMissing, ref oMissing,
                        ref oMissing, ref oMissing, ref oMissing, ref oMissing,
                        ref oMissing, ref oMissing, ref oMissing, ref oMissing);
            stopwatch.Stop();

            Dispatcher.Invoke((ThreadStart)delegate() { WordsList.Items.Add("Dictionary ready"); });
            Dispatcher.Invoke((ThreadStart)delegate() { WordsList.Items.Add(stopwatch.Elapsed); });
            Dispatcher.Invoke((ThreadStart)delegate() { WordsList.ScrollIntoView(WordsList.Items[WordsList.Items.Count - 1]); });
        } // End of function

        public bool CheckWord(string word)
        {
           if (app.CheckSpelling(word))
        {
            doc.Words.Last.InsertAfter(word + '\n');
            return true;
        }
        return false;
        } // End of function

        public void AddLetter(string word)
        {
            CheckWord(word);

            if (word.Length < 3)
            {
                char ch = word[word.Length - 1];

                for (ch = 'א'; ch <= 'ת'; ch++)
                {
                    word += ch;
                    AddLetter(word);
                    word = word.Remove(word.Length - 1);
                } // End of for
            } // End of if
        } // End of function

        private void Window_Closing(object sender, System.ComponentModel.CancelEventArgs e)
        {
            object saveChanges = false;
            doc.Close(ref saveChanges, ref oMissing, ref oMissing);
            thread.Abort();
            app.Quit(ref saveChanges, ref oMissing, ref oMissing);
        } // End of function
    } // End of class
} // End of namespace