:1)you know my family, 2-ая часть отрицательная. 2)i am in the fifth forum, вторая часть отрицательная. 3)pam couldn't stay after lessons, 2-ая часть повествовательная надо до завтра

1)You know my family, don't you?
2)I am in the fifth form, aren't I? (по некоторым учебникам:
   I am in the fifth form, am not I? - но лучше, первое
3)Pam couldn't stay after lessons, could she?

You know my family, don't you?
I am in the fifth form, am not I?
Pam couldn't stay after lesson, could she?