Display or Hide gridlines
Table gridlines make it easier to see where each cell is located in a table if you turned off cell borders.
1. Select the cells whose gridlines you want shown or hidden.
2. Click on View gridlines on the Table tab to display/hide gridlines.
If you hide the gridlines in a table that has borders, you will not see the change because the gridlines are behind the borders. To view the gridlines, remove the borders.