Помогите пожалуйста.
Нужно вписать глаголы.
1.We already (were, have , been ) to London.
2.We ( were, have, been) in London 5 years ago.
3.They (didn't see, haven't seen) the Tsar Bell when they were in Moscow.
4.They (didn't see, haven't seen) the Tsar Bell yet.