It may depend on how your date is formatted. For example, I have a query that looks for records depending on the year that is supplied. My date is formatted like this 12/01/2004. To strip out the year, I do this:
SELECT DISTINCT right([Orders].[Date ordered],4)
FROM Orders;
I'm assuming if I wanted to isolate the month, I'd do something like this:
left([orders].[Date ordered],2).
Hope this helps.