I believe the answer is the Navajo Indians.
The mound-shaped structures are called Hogans.
Hopefully this helped and good luck.
Answer:
having citizens participate in government
Explanation:
The Athenians changed from
being more autocratic to a more democratic system some years after the Spartan War. The Athenian democracy also has the US principle of democracy in which the power belongs to the people .
The people are the ones who elect their leaders, representatives and officials and also participate in some other government functions.
They could make more trips