How can I soundproof the doors that lead from my bedroom to my roommates' bedroom?

Buy some of that blue foam board or pink or silver whatever suits you Put it on the doors with double faced tape. It is insulation board. Then you can also use it for a giant bulletin board.

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I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.