A. AFFIRMATIVE (Краткая форма утвердительных предложений)
a. I'm nine years old.
b. John's a good student.
c. They're teachers.
d. You're my best friend.
e. We're happy today.
B. NEGATIVE (Краткая форма отрицательных предложений)
a. She isn't a doctor.
b. We aren't ready.
c. You aren't five years old.
d. They aren't angry.
e. I'm not a dog.