A question to be answered, schoolwork exercise.
A difficulty that has to be resolved or dealt with.
A puzzling circumstance.
A set of moves required to complete a climb.
Objection.
Difficulty in accepting or understanding or refusal to accept or understand.
Causing a problem; problematic; troublesome.
Difficult to train or guide; unruly.
A regularly scheduled class, in a school, in which discussion occurs of the material covered in a parallel lecture.
The act of publicly reciting something previously memorized.
A part of a song's lyrics that is spoken rather than sung.
The material recited.