Complex sentence: John Topham began his working life as a policeman in the East End of London in the 1920s, where he carried a camera and made photographs of daily life in south-east London, especially around the Sidcup area.
Split into simpler sentences: John Topham began his working life as a policeman in the East End of London in the 1920s. He carried a camera and made photographs of daily life in south-east London, especially around the Sidcup area.