помогите пожалуйста разобраться

Отрицательные формы:

is isn't

are aren't

am am not.

2) My sister is blonde. My sister isn't blonde.

3) His cat is fat. His cat isn't fat.

4) Annd and Tom are ten. Anna and Tom aren't ten.

5) My mum and dad are busy. My mum and dad aren't busy

6) You and I are famous. You and I aren't famous.

7) My dad is a doctor. My dad isn't a doctor.

8) We are hungry. We aren't hungry.

9) You are clever. You aren't clever.

Просто прибавляешь после am, is или are частичку not.

Например:
My sister is not blonde.

Видишь? Я после is поставила not.
Тоже самое сделаешь и с are и с am и с is