Complex sentence: In November 2009, his directive for the party to support the Carbon Pollution Reduction Scheme proposed by the Labor Government split the Liberal Party, leading to a leadership challenge by Tony Abbott on 1 December, Turnbull lost the leadership by one vote.
Split into simpler sentences: In November 2009, he ordered the Liberal Party to support the Carbon Pollution Reduction Scheme proposed by the Labor Government. This decision split the Liberal Party, and following a leadership challenge by Tony Abbott on 1 December, Turnbull lost the leadership by one vote.