The dotted line in the table is the default setting of the table border. If you need to delete the dotted line, there are two ways to do it.

Method 1: Use the table toolbar.

1. First select the table whose border needs to be modified, and then open the table toolbar.

2. In the design tab, find the wireframe button in the border area and click to enter the drop-down menu.

3. Select "No Borders" in the drop-down menu to remove all borders of the table.

Method 2: Use the line drawing tool.

1. Select the cell or the whole table from which you want to remove the table border.

2. Click the "Line Drawing Tool" button and select "No Border" or "Delete Border" from the drop-down menu to clear the table border.

It should be noted that both methods can delete the dotted border in the table, but the visual effect of the table may be affected after deleting the border, so please carefully evaluate the scope and influence of deletion before using it. In addition, these operations may be different depending on the software version used, and the specific methods can be adjusted according to the specific software version.