We have all experienced days when everything goes wrong.|我们都有特别不顺的日子。
We have all experienced days on which everything goes wrong.
We have all experienced days that seemed like years.
Days seemed like years.直接用that/which
There was a time when (曾几何时）the owners of shops and businesses in Chicago had to pay larg sums of money to gangsters in return for ‘protection’.
Aunt Harriet lived in that leisurely age when servants were emplyed to do housework.
This is the reason why I didn’t come here.
This is the reason why I lied.
This is the cause
why I like you.