normal subsystem

例句：

1. 1. The temperature is normal for this time of year.
   这个季节的气温是正常的。
2. 2. She wears a normal dress for the occasion.
   她穿着一件普通的连衣裙参加那个场合。
3. 3. The normalcy of life has been disrupted by the pandemic.
   生活的日常秩序因疫情而被打乱。