First, the order of subgroups is the divisor of 6: 1, 2, 3, 6.

Secondly, the generator of subgroup H 1 of order 65438 is A 6 (the 6th power of A) = E, so H 1={e}.

The generator of the second-order subgroup H2 is a 3, so H2 = {e, a 3}.

The generator of subgroup H3 of order 3 is a 2, so H3 = {e, a 2, a 4}.

The generator of subgroup H4 of order 6 is a, so H4 is the original group itself {e, a, a 2, a 3, a 4, a5}.