Complex sentence: Polygyny, the practice of one husband taking multiple wives, has been condemned as being a form of human rights abuse and many international human rights organisations as well as Women's rights groups in many countries have called for its abolition.
Split into simpler sentences: Polygyny, the practice of one husband taking multiple wives, has been condemned as a form of human rights abuse. Many international human rights organisations, as well as women's rights groups in many countries, have called for its abolition.