Complex sentence: De Angelis began her career in the 1980s as an actress with the Monstrous Regiment theatre company but in 1987 her play "Breathless" was a prize winner at the 1987 Second Wave Young Women's Writing Festival.
Split into simpler sentences: De Angelis began her career in the 1980s as an actress with the Monstrous Regiment theatre company. In 1987, her play "Breathless" was a prize winner at the 1987 Second Wave Young Women's Writing Festival.