The article The Internal Structure of English Nouns: What Prototypical Nouns Look Like in the English Language explains the internal structure of prototypical English nouns.

The articles Forming Plurals of Regular Nouns in English: Morphological, Spelling, and Pronunciation Changes and Forming Plurals of Regular English Nouns: Suffixation to Create Plural Nouns in the English Language explains how to form the plurals of regular English noun through suffixation and slight spelling changes.

The articles Forming Plurals of Irregular Nouns in English: Morphological, Spelling, and Pronunciation Changes and Forming Plurals of Irregular English Nouns: Stem and Ending Changes to Create Plural Nouns in English explains how to form the plurals of irregular English nouns through stem changes and ending changes.

The articles The Internal Structure of Noun Phrases in English and The Noun Phrase in English: Describing Nouns with Determinatives, Modifiers, and Complements explains the seven grammatical forms that function as determinatives, noun phrase modifiers, and noun phrase complements in English noun phrases.

The article Grammatical Noun Phrase Complement in English: Completing Nouns with Prepositional Phrases and Noun Clauses explains the two grammatical forms that can function as the grammatical noun phrase complement in English.

The article Teaching Preschoolers about Nouns as People, Places, and Things provides a lesson plan for teaching preschoolers the basics about nouns in English.

Grammatical Functions

The article The Functions of Nouns and Noun Phrases in English identifies and describes the ten main grammatical functions of nouns and noun phrases in English grammar: subject, subject complement, direct object, object complement, indirect object, prepositional complement, noun phrase modifier, possessive modifier, appositive, and adverbial.

The article English Nouns and Noun Phrases: The Ten Functions of Nouns in English Grammar also explains the ten grammatical functions of nouns and noun phrases in English grammar.

The article English Adverbials: Noun Phrases, Verb Phrases, and the Positions of Adverbials explains the use of noun phrases as adverbials in English.

Pronouns

The article The English Personal Pronoun System for ESL Students describes the grammatical forms and grammatical functions of the personal pronouns in English grammar.

The article The English Pronoun System: Subject, Object, Possessive, and Reflexive Pronouns in English explains the four types and grammatical functions of personal pronouns in English grammar.

The articles The Indefinite English Pronouns for ESL Students and The Indefinite English Pronouns: The Forms and Functions of Indefinite Pronouns in English explains the seven forms and six functions of indefinite pronouns in English grammar.

The article The Demonstrative English Pronouns for ESL Students lists and explains the four demonstrative pronouns in English.

The article The Interrogative English Pronouns for ESL Students lists the five interrogative English pronouns and explains the six grammatical functions of interrogative pronouns in English grammar.

The article The Forms and Functions of Conjunctions in English touches on relative pronouns as being subordinating conjunctions that perform the grammatical function of subordinator.

The article The Syntactic Functions of Relative Pronouns in English explains the five syntactic functions of relative pronouns: subject, direct object, prepositional complement, possessive determiner, and adverbial.

Noun Clauses

The article The Forms and Functions of Noun Clauses in English explains the eight main grammatical functions of noun clauses in English grammar: subject, subject complement, direct object, object complement, indirect object, prepositional complement,  adjective phrase complement, and noun clause complement.

The article The Eight Functions of Noun Clauses in English: The Nominal Functions of Subordinate Clauses in English Grammar explains eight grammatical functions of noun clauses in English grammar: subject, subject complement, direct object, object complement, indirect object, prepositional complement, adjective phrase complement, and appositive.

The article The Forms and Functions of Clauses in English: Verb Clauses, Noun Clauses, Adjective Clauses, and Adverb Clauses explains the eight grammatical functions of noun clauses in English grammar.