1. 
Omar:  There is so much we need at the store.
Maria: What do you mean? What do we need?
Omar:  We need a package of spaghetti, for one thing.
Maria: OK, I'll write it on the list. What else?

Practice:

1. 
A: There is so much we need at the store.
B: What do you mean? What do we need?
A: We need _________, for one thing.
B: OK, I'll write it on the list. What else?