So + predicative + subject expressed by a noun
e.g. Her joy was so great that she stood fascinated. - So great was her joythat she stood fascinated.
A.1. The summer night was so hot and still that through every opened window came in but hot air (Galsworthy). 2. His remarks were so strong that she, startled, relapsed into silence (Mitchell). 3. Her Dutch is so rusty she can no longer speak it (Parker). 4. After an hour Scarlett’s hands were so swollen and bruised she could hardly flex them (Mitchell).