Read the text. Put the verbs in the proper Passive forms. Explain why you have preferred one form to another.
The Tower of London 1 (to build) by William the Conqueror in 1078 as a castle and palace. Since that time it 2 (to expand) to its present size, and as an armory, a zoo, a royal mint, a prison and a museum. At the time when it was a prison a lot of people 3 (to lock) in the Tower. Anne Boleyn, Sir Walter Raleigh and Elizabeth the First 4 (to shut) there, too. Spies 5 (to imprison) in the Tower during the World Wars. Many convicted 6 (publicly/to execute) on the Tower Hill. They 7 (to behead) with the block and axe, which 8 (to keep) and 9 (to show) in the Tower of Armory now.