load html file into content place holder

i have a word document that i transform it to an html file but i dont know how to insert it into a content place holder
i try 
Label mylbl = new Label();
        mylbl.Text = "Hello";

ContentPlaceHolder cd;
cd = (ContentPlaceHolder)Master.FindControl("ContentPlaceHolder1");

cd.Controls.Add();
outside the content place holder i just write Respose.WriteFile("filename.html"); and it work  but i dont know how to add the html document into the content place holder.
if someone can help me please



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