The 3rd and 9th Amendment
Crystal Harmony Schirmacher
The Third Amendment- Quartering Troops
I think this means that a solider should not be living in one's home during peace and in war without the home owner's consent.
You wouldn't really use this anymore, but its always a possibility that our country can go into a big war here.
The 9th Amendment
It basically states that no rights will be taken away. It prevents the government from expanding their power. It provides and enforces rights not spoken about in the constitution.
You would use this right when the government starts taking away rights.