Noun: name of a place/animals/things etc..
Example :
He is ram.(ram is the noun here .because it is a name of a person)
Pronoun: replaces the noun .
Example :
He is a boy.(here He is the pronoun)
Verb : action words.
Example:
He can't run.(here run is the verb)
Adverb :modifying a very to give more meaning.
Example:
He is a fast runner.