Tables appear frequently in inFlow, for example, for entering lines in an order.
 

To add a new line into a table, click into the row at the bottom of the table with the  icon next to it.  Then, you can start typing into this row.  Once any changes have been made, the new row will be preserved and the  icon will move to the row underneath it.

To delete a row from the table, you must first select the entire row.  Select a row by clicking on the gray box at the left edge of the row (the row header).  To select more than one row, click on the row to select and drag the mouse to select other adjacent rows.  To select all rows in a table, click in the cell at the top left corner of the table.  Once you have selected the rows to delete, you can delete the rows by right clicking and select Delete Selected Rows or by pressing the Delete button on your keyboard.