Detailed Instructions: In this task, you are given a question and a context passage. You have to answer the question based on the given passage.
Problem:Whats needed to understand a group by it's presentation, Context: Quotient groups and subgroups together form a way of describing every group by its presentation: any group is the quotient of the free group over the generators of the group, quotiented by the subgroup of relations. The dihedral group D4, for example, can be generated by two elements r and f (for example, r = r1, the right rotation and f = fv the vertical (or any other) reflection), which means that every symmetry of the square is a finite composition of these two symmetries or their inverses. Together with the relations
Solution:
Quotient groups and subgroups