Complex sentence: Because Jive Records wouldn't pay session singer Mary Kiani enough money to be a full-time member of the act, she was forced to leave the group she was replaced with Debbie Millar, a 25 year old singer from the south coast Bournemouth.
Split into simpler sentences: Because Jive Records wouldn't pay session singer Mary Kiani enough money to be a full-time member of the act, she was forced to leave the group. She was replaced with Debbie Millar, a 25 year old singer from the south coast Bournemouth.