My problem is simple, but the explanation isnt that much...

I have a document called base.xls, and its composed of two columns. Column A
is the string key, and column B is the string translation.

Now i have a series of other documents that are composed of several columns,
but then again columna A is the string key, and column D is the string
translation.

What i need to do is to create a routine at base.xls that can be used to
compare column A from both documents, and if they match, put on the D cell
of the second kind of document the text that is in the B cell of base.xls

Also, i need to be able to change what document im comparing, because i have
like 5 or 6 of the type 2 documents every week, and all need the string
translation .

Could anyone help me?