building form/subform

[gatarossi]

Dear all,

I'm having problem with building a form:

In my database I have these tables:

1) expense_code - fields: expense_code, expense_description
2) profit_center - fields: profit_center_code,
profit_center_description
3) period - fields: period
4) expenses_control: - fields: expense_code, profit_center, period,
values_USD

I made a relationship between the fields in the three first tables
with the last table, the name of the fields are the same.

Then I have tried everything to do a form/subform to update/include/
exclude values in my table expenses_control (since Mai/07!). My
problem is that I need that the form/subform has this layout (more or
less an Excel´s sheet):

Form:
profit_center (combobox): the user will select the profit center
period (multiselect listbox): the user will select as many dates as he
wish, and for each date selected will appear one column in the subform

Subform:
expense_code first date selected second date selected third
date selected ...
salary 100
110 120
taxes 50
60 70
..
..
..

Is it possible?

Thank you.

André.