在雨天用on。表示具体的某一天用on。
例：I like to have my boots and umbrella on a rainy day.
我喜欢在雨天穿雨鞋，打雨。
相关介绍
They reached the nature park in Shishou on a rainy day.
他们在一个雨天到达了石首的天然公园。
The story is about a cat who tries to entertain two children on a rainy day while their mother is away from home.
这是一个关于一只猫的故事。在一个雨天，两个小孩儿的妈妈不在家，这只猫想要逗他们开心。
There is no question of our leaving on such a rainy day.
在这样的雨天我们是不可能动身的。
