Complex sentence: Stephen Joseph Harper (born April 30,1959) is a Canadian politician who is the 22nd Prime Minister of Canada since 2006, and was the Leader of the Conservative Party from 2004 to 2015.
Split into simpler sentences: Stephen Joseph Harper (born April 30,1959) is a Canadian politician who is the 22nd and current Prime Minister of Canada. He was the Leader of the Conservative Party from 2004 to 2015.