1.No, it isn't Saturday today
Is it Saturday today?
Isn't it Saturday today?
2. No, it isn't five o'clock
Is it five o'clock?
Isn't it five o'clock?
3. No, it isn't time to go to school
Is it time to go to school?
Isn't it time to go to school?
4. No, it isn't time to begin our lesson
Is it time to begin our lesson?
Isn't it time to begin our lesson?
5. No, it isn't difficult.
Is it difficult?
Isn't it difficult?
6. No, it isn't winter
Is it winter?
Isn't it winter?
7. No, it isn't time to go to bed
Is it time to go to bed?
Isn't it time to go to bed?
К сожалению, не знаю точно ли это. Удачки)