I'd like to rearrange some of us between the rooms. Originally, A, B, and C were in the triple room, while D and E were in the double room. Now, I'd like to have A, B, and D in the triple room, and C and E in the double room.
こんにちは！
ご質問ありがとうございます。
ご質問について、いくつか言い方が考えられますが、例えば、
I'd like to rearrange some of us between the rooms. Originally, A, B, and C were in the triple room, while D and E were in the double room. Now, I'd like to have A, B, and D in the triple room, and C and E in the double room.
とすると、『各部屋に泊まる人の変更をしたいです。当初、A,B,そしてCが3人部屋でDとEは2人部屋でしたが、A,B,とDが3人部屋で、CとEを[2人部屋](https://eikaiwa.dmm.com/uknow/questions/27546/)に変更したいです。』と言えます。
役に立ちそうな単語とフレーズ
rearrange 配置を変える
参考になれば幸いです。
日本 
