MenuStrip in vb 2005

hi,

I am using vb 2005
I have doubt in MenuStrip in vb win form.
In my MDI form have 3 main menu items and one of my child form has one menu..
i want to merge that one menu in to MDI form's menu, when i maximize child form.
child form's menu must come in 3rd position of the main menu.Then there will be total 4 menu.
Then how to merge that single menu in to main menu