rain 可作動(dòng)詞也可做名詞
－動(dòng)詞：It will rain today.今天會(huì)下雨
—名字：The rain is smaller now.現(xiàn)在雨下小了.
raining是rain作為動(dòng)詞的進(jìn)行時(shí)態(tài)
It is raining heavily outside.現(xiàn)在外面雨很大.
rainy是形容詞
It is a rainy day.今天是個(gè)雨天
估計(jì)初中的填空選擇會(huì)這樣出題：
I can go swimming with you tomorrow because the weather report said it will _____.（這里填rain,為動(dòng)詞）
I can go swimming with you tomorrow because the weather report said it will be a ____ day.(這里填rainy.為形容詞)
I can go swimming with you today because it is _____ outside.(這里填raining,動(dòng)詞進(jìn)行時(shí)態(tài))