Hi Natalia! This is an interesting topic!
Fillmore adds some examples of syntactic problems in which case analysis is useful. Among these are parallel sentences with "have" and "be":
Many toys (O) are (V) in the box (L)
The box (L) has (V) many books (O) in it (L-copy)
These two parallel sentences have the same case frame but different choice of subject.
From: Case gramma Theory - Walter A. Cook - page 7
http://books.google.com.ar/books?id=S_lRAXSpymkC&printsec=frontcover&dq=%22ca se+grammar%22+%22verb+to+be%22&source=gbs_summary_ r&cad=0#PPP1,M1
Hope this helps!
