Пожалуйста, помогите люди! Дам 50 баллов!!!!!!
Choose the right form of the verb and write down the sentences!!!!!!
1. We already ( where, 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.

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