Ответ:

2. dirtiest

3. more expensive

4. noisiest

5. slower

Объяснение:

2. This is the most exciting book I have ever read.

3. It's the most beautiful building we have ever seen.

4. That is the funniest joke you have ever told.

5. It's the most beautiful photograph I have ever taken.

6. That is the most stupid thing I have ever done.

7. That is the most delicious meal she has ever made.

8. These are the best poems he has ever written.