Hello - I have Word 2010, so it might be a bit different and I hope I interpreted your question correctly.
After pasting info from Excel into World, highlight the info by clicking the box on the top left corner grid. Go to the highlighted Table Tools tab on the top right of the ribbon. Go to the Layout tab. Then click the second option from the left 'View Gridlines'.
Let me know if I even got close to answering your question.
Have a great day!