When you need to merge complete Microsoft Word documents, you could, of course, copy and paste them together, or you can use this simpler method that works with MS Word 2007 and 2010.
1. Create or open the Word document where you want to merge the files. Place your cursor on the document where you want the text inserted. On the Word toolbar, select the Insert tab.
2. On the right-hand side of the toolbar, go to Object and click the arrow to access the drop down menu. Select Text from File.
3. In the dialogue window that opens, find the document you want to copy on your hard drive, select it and click the Insert button. The text will be copied where you want it. If you are adding more text, place your cursor where you want to add it and repeat Step 3.