Complex sentence: He was originally elected Labour Member of Parliament for Newcastle-upon-Tyne East in the October 1974 general election, but in 1981 he was among a number of Labour MPs who defected to the new Social Democratic Party.
Split into simpler sentences: He was originally elected Labour Member of Parliament for Newcastle-upon-Tyne East in the October 1974 general election. In 1981 Thomas was among a number of Labour MPs who defected to the new Social Democratic Party.