WORD: Display Document Line Numbering
Displaying line numbers in the margin of your Word document is an easy way to refer to specific lines in the document.

To display line numbering in the current document:

1. Open a Word document.

2. From the menu bar, click Format -- Document. Click the Layout tab near the top.
    Click the Line Numbers button on the left side of the window.

3. Near the top of the Line Numbers window, click to check the box next to Add line numbering.
    Select how the numbers will display in the document by clicking one of the buttons in the Numbering section.
    Modify the other options as you wish. Click the OK button.

4.  Your document now displays line numbers in the left margin.  See the example below.
 lines2 lines3 

  5. Follow the same steps shown above to remove the line numbers, except in step 3 uncheck the box next to Add line numbering.