Adding new fields to table help!!!!???

[jims]

I am trying to add a new field to a table in my database
but when I try to use the design view, the windows prompt
me that the table's property can't be changed because
it 's linked table.
Then I try to open the TABLE.mdb file directly to change
it but the windows prompt me that it 's just a copy of the
table (all tables with a yellow mark of a double arrow)
and I can only open it in read only mode.
I want to ask where and how can I change and add the
fields to the table for my database ????
Thanx a lot