chase rainbows
做白日梦，追寻一些遥不可及的事情
natural phenomenon
自然现象

sunrise 日出
sneak the sunrise past the rooster:
means to do something extremely difficult or impossible
字面意义是逃过公鸡的日出。因为清晨日出公鸡先知，没有日出是逃得过公鸡的眼睛的。所以它用来比喻表示尝试做不可能的事或者狡猾地暗中做某事。

raining cats and dogs 瓢泼大雨
It means it's raining very heavily.
倾盆大雨，瓢泼大雨

lightning 闪电
as swift as lightning
风驰电掣，快如飞箭。

thunderstorm 大雷雨;雷电交加的暴风雨
sit there like a dying duck in a thunderstorm
惊慌失措的，要死不活的样子

fog 雾
somebody is in a fog:
means the person is confused
表示某人非常疑惑不清楚

flood 洪水
flood the market 充斥市场