When text is selected within a cell, cutting, copying, and pasting actions are the same as for text selected outside a table. You can also cut, copy, and paste cells and their contents. If the insertion point is in a table when you paste, multiple pasted cells appear as a table within a table. You can also move or copy the entire table.
To embed a table within a table, place the insertion point in the cell where you want the table to appear, and then choose Edit > Paste.
To replace existing cells, select one or more cells in the table—making sure that there are sufficient cells below and to the right of the selected cell—and then choose Edit > Paste.