private void TablesAndCells( string file, int tableIndex )

    {

      using( var document = DocX.Load( file ) )

      {

        // Get the table to modify

        var table = document.Tables[ tableIndex ];



        // Merge the first 3 cells of the first row

        table.Rows[ 0 ].MergeCells( 0, 3 );



        // Merged the last 2 cells in the third row

        var columnCount = table.Rows[ 1 ].ColumnCount;

        table.Rows[ 2 ].MergeCells( columnCount - 2, columnCount - 1 );



        // Merge the first cell of rows 2 and 3

        table.MergeCellsInColumn( 0, 1, 2 );



        // Save the changes to the document

        document.Save();

      }

    }