Choose the right form of the verb  and write down the  sentences                                                1.we already (were, have been) to London.                                                                          ...

Choose the right form of the verb  and write down the  sentences                                                1.we already (were, have been) to London.                                                                               2.we (were,have been) in London 5 years ago .                                                                       3. they (didn't  seen,haven't    seen) the Tsar Bell when the were in Moscow.                              4. the ( Didn't seen, haven't seen) the Tsar  Bell yet.