So for example, if I'm speaking in English, I have to speak grammatically differently if I'm talking about past rain, "It rained yesterday," current rain, "It is raining now," or future rain, "It will rain tomorrow."
例如，在英语中需要用明确的语法变化来表示不同的时态， 如果我说过去下过雨：“It rained yesterday” 正在下雨：“It is raining now” 将要下雨：It will rain tomorrow.”