WPF richtextbox 换行问题

C# code

Run run1 = new Run(user.NickName + "   " + DateTime.Now.ToLongTimeString() + "\r\n");
TextBlock text1 = new TextBlock();
TextBlock text3 = new TextBlock(new LineBreak());
text1.TextWrapping = TextWrapping.Wrap;
text1.Inlines.Add(run1);
text1.Inlines.Add(new LineBreak());
                   
text1.Foreground = Brushes.DeepSkyBlue;
Run run2 = new Run(tr.Text);
// ext1.Inlines.Add(run2);
TextBlock text2 = new TextBlock(run2);
para.Inlines.Add(text1);
//para.Inlines.Add(text3);
para.Inlines.Add(text2);
FlowDocument doc = new FlowDocument(para);
richTextBox1.Document = doc;
richTextBox1.ScrollToEnd();

我要这种格式：

浪淘沙 22:15:18
sadsdasdasddddddddddddddddd
浪淘沙 22:23:12
sadsdasdasddddddddddddddddd
浪淘沙 22:27:18
sadsdasdasddddddddddddddddd

不知道！学习了！