Entity in another entity record in dynamic crm 2011

Senario:

ex: opportunity and opportunity product

look like here we need to give new_Subcooldrink entity in the form of new_Cooldrink entity

for this first we need to create new_Cooldrink entity

after that create new_subcooldrink  enity.
here we need  not to give the display area.

save it and give the required attributes

give the N:1 relation ship from

new_subcooldrink to new_cooldrink 


then customize the cooldrink form. Insert  the Sub Grid