Hi there, i want to create an input form for a client of mine

Every row is one entry, and one of the cells (hence the whole column) needs to be a combo box. I have managed to create a combo box and attach it to one cell. Lets say B2.

However i cannot do what would seem a simple thing. I am a newbie...
For the reason that i cannot know before hand how many rows my client will want to use, i want him to be able to copy paste a row and instantly the new combo box to be attached to the appropriate cell...For example if i copy ROW 2 and paste it to row 3, i would like the new combo box to be linked to B3.

Should be simple i guess...