Access

Hello I was wondering if you could help:

i have a form containing 'service information' on equipment at offices like fire extinguishers etc (includes date of last test, equipment provider, Supplier, equipment type and period of review)on 'equipment' at 'offices'.

I also have a subform which shows the (all) 'date of the last test' for this product. i want the two forms to work together so i can enter a date in the 'date of last test' on the main form and it will enter it as a new records on the subform and store the prevoius date still in this subform. is that possible?
Thank-you