The word "rain" can be a noun or a verb. For example, in the sentence, "I like rain." it is a noun. In the sentence "It is going to rain." it is used as a verb.
In the rain is a prepositional phrase
It is a noun.
"Drizzle" can be a noun or a verb. As a noun, it describes a light rain, and as a verb, it means to rain lightly.
Rainstorm is a noun. Nouns are people, places, and things.
In this sentence "it" is used as the subject of an impersonal verb and is therefore a pronoun.
The part of speech for this particular word is a noun.
part of speech
Rain is usually a noun, but can be a verb, as It's starting to rain.
The part of speech for "answer" is a noun.
what part of speech is beneath
adverb
The part of speech for "explicit" is an adjective.