rain可以做名词和动词，做名词时意思就是雨水，做动词时意思为下雨。rainy是形容词，表示下雨的，多雨的。raining是动名词，是rain的现在分词形式，表示正在下雨。

rain的用法例句

1. The recent rain had churned up the waterfall into a muddy whirlpool.

最近的一场雨把瀑布搅成了泥水漩涡。

2. She was born in the middle of a rain storm.

她出生在一场暴风雨中。

3. He stared at the rain spattering on the glass.

他凝视着雨点溅落在玻璃上。

4. His hair was plastered down to his scalp by the rain.

他的头发淋雨后紧贴在头皮上。

5. Acid rain is not straightforwardly attributable to the burning of coal.

酸雨并非简单地由烧煤造成。

rainy的用法例句

1. Summer is a rainy season in China.

在中国，夏天是一个多雨的季节。

2. A rainy day is cold in this season.

这个季节雨天很冷。

3. The rainy season in the Andes normally starts in December.

安第斯山脉的雨季一般从12月开始。

4. It's rainy in Guangzhou now.

广州正是多雨的时候。

5. It's either cloudy or rainy.

要么阴天要么下雨。