Disagree using anything, nothing, anybody, nobody.

Решение:

1. Alice bought something tasty.
   a) Alice didn't buy anything tasty.
   b) Alice bought nothing tasty.
2. There was somebody in the room.
   a) There wasn't anybody in the room.
   b) There was nobody in the room.
3. I can hear something.
   a) I can't hear anything.
   b) I can hear nothing.