Вставим глагол-связку am, is, are в предложения.
- Tim and Tom <strong>are</strong> brothers.
- His brother Tim <strong>is</strong> a student.
- His brothers <strong>are</strong> eight.
- My mother <strong>is</strong> happy.
- My mother and I <strong>am</strong> friends.
Ответ: смотри решение в ответе