Using A Macro To Insert Checkboxes?

I'm trying to use VB to create a macro that will insert check boxes automatically when data is entered in that row. The problem is that I have VERY little experience with VB code. Here's what I'm looking for:

When I enter data in box A2, I want to automatically put a check box in cells D2, F2, G2.
When I enter data in box A3, I want to automatically put a check box in cells D3, F3, G3.
(and so on....)

I have already found a macro that will put a check box in a particular cell, I just need to figure out how to do it automatically in the cells I want. Here's what I have to put the check boxes in:

Sub AddCheckBoxes()
On Error Resume Next
Dim c As Range, myRange As Range

[Code]....

I just want that to happen in the 3 cells in the same row that I enter data in automatically when I enter data.