You are on the right track. Use a form and subform. Base the form on the person table, and base the subform on the table linked to the person table with a foreign key.
Then drop the subform on the main form in design view, and make sure that the parent and child fields are linked. Then you can add new people in the main form, and add items for the person in the subform.
If the query is from more than one table on your form, it won't be updateable.
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