Complex sentence: Monsen started her working life as a graduate teacher and arrived in China on 1 September 1901 where she began a three-term, 30-year mission becoming an important figure in the history of the charismatic renewal in China.
Split into simpler sentences: Monsen started her working life as a graduate teacher and arrived in China on 1 September 1901. She began a three-term, 30-year mission, becoming an important figure in the history of the charismatic renewal in China.