Complex sentence: The robbers rotate the hostages between various rooms and occasionally insert themselves covertly into the groups, while also taking turns working on an unspecified project involving demolishing the floor in one of the bank's storage rooms.
Split into simpler sentences: The robbers rotate the hostages between various rooms and occasionally insert themselves covertly into the groups. The males take turns working on an unspecified project involving demolishing the floor in one of the bank's storage rooms.