Open the document for editing and place the cursor in the cell above which you want to insert a new row. Activate the Home tab on the toolbar and scroll to "Cell". Click on the "Insert" button. A new row will be added.
You can also select several adjacent cells and click on the button "Paste". Please note: if you selected multiple cells in the row will be added one new row. If you select several adjacent cells in several rows, will be added the same number of rows that were selected. But if the selected cells will be more vertically than horizontally, will be added not rows and columns.
Not to be mistaken or confused when adding multiple empty rows, it is better to highlight the number of cells vertically and click on the arrow in front of the button "Paste" in the section "the Cell". Unfold the context menu. Select "Insert rows on the sheet".
There is another way. Move the cursor to the left edge of the working region of the sheet where the ordinal numbers of the rows. Wait until the cursor changes to an arrow pointing to the right. With the left mouse button, highlight one or more rows.
Click the right mouse button on selection and choose context menu item "Paste". Just don't confuse it with the command "Paste from clipboard", next to the desired menu item is not worth any of the thumbnails.
If you created a table using the tool "table" on the Insert tab, point not to the sequence of the row numbers and to the left edge of the table. Wait until the cursor changes.
Then click the right mouse button in the highlighted row and select from the drop down menu "Insert" and sub "table Rows above."