Объяснение:

4)

1 more

2 the colder

3 more

4 heavier, the heaviest

5 better, the best

6 worse, the worst

7 the cheapest, slower

1. She thinks Science is worse than Maths

2. Mark is the best singer in our class

3. The most exciting day in the year is my birthday

4. Mice and tigers are smaller than elephants

5. Mary is the youngest person in their family

6. Dolphins are more intelligent than hippos