3. Fill in the comparative or superlative form of adjectives.

Решение:

Используем сравнительную или превосходную степень прилагательных:

1. Mark is more intelligent than him.
2. She is the tallest girl in the class.
3. He ran the fastest of all.
4. Avril Lavigne is the most attractive singer in the world.
5. He speaks more quietly than his brother.
6. Ann is more beautiful than Linda.
7. They are the most famous Russian figure skaters.

Ответ: more intelligent; the tallest; the fastest; the most attractive; more quietly; more beautiful; the most famous.