Weather in English, such as: when does rain snow use ing form? When to use noun forms. When to add s and when to use prototype

Use ing to express the present continuous tense and noun form respectively. For example, it is raining now! It's raining heavily today! Add the s table to the simple present tense. For example, it rains today! Rain is an uncountable noun, so you can't add S. Usually, adding S indicates the simple present tense. Use the prototype, such as a little rain!