وَتَزِيدُ عَلَيْهِ الْأَمَةُ الْبَطْنَ وَالظَّهْرَ
The source also gives a separate Awrah rule for the historical legal category of an enslaved woman: the male boundary plus the abdomen and back. This is retained because the course is teaching the classical text accurately; it is a historical fiqh category, not a modern learner instruction or a rationale for contemporary dress.