6) 2-me, 3-them, 4-her, 5-us
7)2-Are you taller than your teacher? 3-Are you older than your friend? 4-Is your friend more hard-working than you? 5-Is your hair longer than your friend's hair? или Is your friend's hair longer than your hair?
8)2-No, I am not (если вы ниже учителя) Yes, I am (вы выше)
3-No, I am not (если вы младше вашего друга) Yes, I am (вы старше)
4-Yes, he is
5 -Yes, it is