1·Yeah, when pigs fly!
猪可不能飞起来！
2·When would they be hired again? Perhaps, as the saying goes, when pigs fly.
他们什么时候会被重新雇用？也许正像俗话说的，等到猴年马月吧。
—— 《柯林斯英汉双解大词典》
3·Shannon: Sure I can. When pigs fly.
夏侬：当然可以。等猪会飞天再说吧。
4·She will come to your birthday party when pigs fly.
她是不会来参加你的生日聚会的，除非太阳从西边出来。
5·When pigs fly - about something that will never happen.
除非猪都会飞了表示某事永远都不会发生，绝无可能。
6·When pigs fly - about something that will never happen.
除非猪都会飞了——表示某事永远都不会发生，绝无可能。
7·Example: The things you want to create is can only be complete when pigs fly.
例：你要是能那些事做完，那猪都会飞了。
8·When pigs fly: From its apparent epicenter in Mexico, swine flu has taken flight across the oceans.
猪飞的时候：从墨西哥明显的疫中区，猪流感搭乘飞机越过了海洋。