Вот правильные варианты ответов:
- The 1-st of September isn't the longest day.
- The mouse is smaller than the cat.
- It is a very funny English book.
- He is a nice boy.
- My hands are cleaner than your hands.
- Russia is the largest country.
- In the city the rivers are dirtier than in the country.
- Ted is the worst pupil in our class.