YOU SAID:
No one else was in the room where it happens
INTO JAPANESE
それが起こる部屋には誰もいなかった
BACK INTO ENGLISH
There was no one in the room where it happened
INTO JAPANESE
それが起こった部屋には誰もいませんでした
BACK INTO ENGLISH
There was no one in the room where it happened
You should move to Japan!