昨天当我走进房间时母亲正在做饭的翻译：Yesterday when I walked into the room, the mother is cooking 什么意思？中文翻译英文，英文翻译中文，怎么说？

青云英语翻译

Yesterday when I walked into the room when my mother was cooking

Yesterday when I walked into the room, the mother is cooking

When yesterday I entered the room the mother was preparing food

Yesterday when I walked into the room, the mother is cooking