This book is more interesting than that one.
He wrote his test worse than his friend.
There were less dictations in English than in Russian.
She is the best friend.
He bought the most expensive car.
My Granny is the eldest in our family.

Сравнительная:
Nick is better in math,than his sister.
Mike is worse in cooking,than his friend Jack.
The sky today is more beautiful,than yesterday.
Превосходная:
My puppy is the happiest member of my family.
That book is the most interesting for me.
Ann is the best student in our class.