Complex sentence: She has held the world record in the 5000m walk since 2002 and won a silver medal at the world championship in 2003 over 20km.She was also the first Irish athlete to win a medal in the walk at an Athletics Championship.
Split into simpler sentences: She has held the world record in the 5000m walk since 2002 and won a silver medal at the world championship in 2003 over 20km. O'Sullivan was also the first Irish athlete to win a medal in the walk at an Athletics Championship.