Скажите что это не так..
There is a doll on the chair.
There was a cake on the table.
There were sweets in the bag.
There are sweets in the bag.
There was a puppy in the box.

There isn't a doll on the chair. There wasn't a cake on the table. There weren't sweets in the bag. There are not sweets in the bag. There wasn't a puppy in the box.