Adding and deleting rows in a worksheet
Add row
Right-click in the worksheet and select Insert Row from the menu.
Or
With a row, column, or cell selected, click 
in the main toolbar.
If a cell is selected, the row is inserted above the selected cell. If multiple rows are selected, the same number of rows will be inserted above the first selected row.
Delete row
1. Right-click a cell in the row and select Delete from the menu.
2. In the dialog, select the Selected Row(s) option button and click OK.
Move rows
1. Select the contiguous rows.
2. Move the cursor over the lower right corner of the selected block of rows and, when the cursor changes to a four-arrow sign, drag the block of rows to the new location.