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Sure! Here’s the completed text with the past perfect simple or continuous forms: TENTH DOCTOR Before he became the Tenth Doctor, actor David Tennant (0) had always wondered what it would be like to play the part of Doctor Who, a Time Lord from the planet Gallifrey. He knew that many different actors (1) had played the role since the programme was first shown in the 1960s. Luckily, Time Lords have the ability to "regenerate" their bodies, so that if killed they can come back to life again, although their bodies may change. This amazing ability meant that the programme makers at the BBC (2) had replaced one Doctor after another without any problem. However, Christopher Ecclestone (3) had acted the part of the ninth Doctor for only a few months when he decided to leave. The reaction to the new series was good so the BBC were worried about who could take over. Christopher and Billie Piper (4) had not worked together for very long but they (5) had become good friends and they were popular with the viewers. No one (6) had imagined that Christopher would leave so soon, so the programme makers (7) had not thought of a replacement. How could they find someone else so popular? David (8) had been watching the new series of Doctor Who since the very first episode. He (9) had always loved the programme, even as a small boy. In fact, David (10) had wished to be the Doctor since he was three or four years old, so when his agent phoned him with the offer, he was amazed and delighted. The Tenth Doctor was very bit as popular as the previous ones, even after Billie Piper (11) had left. There is only one small problem on the horizon: Time Lords can only 'regenerate' thirteen times, and nobody knows what will happen then!