The subject is the part of the sentence that performs an action or which is associated with the action.
<subject> = <simple subject> | <compound subject> <simple subject> = <noun phrase> | <nominative personal pronoun>
The nominative personal pronouns are: I, you, he, she, it, we, they. The pronoun "you" is used to refer to one (singular) or many persons (plural). "He", "she", and "it" are used to refer to masculine, feminine, and neuter nouns, respectively. English nouns do not have a grammatical gender, but singular nouns that represent masculine subjects (king, boy) are referenced with the masculine pronoun "he". Nouns representing feminine subjects (queen, lady) are referenced with the pronoun "she". Inanimate objects in singular form (table, chair) are referenced with the pronoun "it".
In any of the descriptions of the subject where a noun can be used, the <noun> may be substituted by a noun followed by any number of prepositional phrases:
<noun> = <noun> [<prep phr>*]
In this way we can generate noun phrases such as "Tarzan of the jungle", "the difficult chapter in the book", etc. These constructions might be said to consist of a "noun phrase" and a "prepositional phrase" in a traditional grammar. Similarly, we may substitute the following for any occurrence of <adjective>:
<adjective> = <adjective> ("and" | "or") <adjective>
This enables the formal description to generate noun phrases with adjectives joined by conjunctions, such as "a very beautiful and intelligent lady". Prepositional phrases consist of a preposition followed by an object. Objects are defined under complements.
<prep phr> = <preposition> <object>
A "noun phrase" is generally defined as a syntactic unit that includes a noun. The formal definition of a noun phrase given below describes the most common components of a noun phrase.
<noun phrase> = "the" <specific proper noun> | <proper noun> | <non-personal pronoun> | <article> [<adverb>* <adjective>] <noun> | [<adverb>* <adjective>] <noun-plural> | <proper noun-possessive> [<adverb>* <adjective>] <noun> | <personal possessive adjective> [<adverb>* <adjective>] <noun> | <article> <common noun-possessive> [<adverb>* <adjective>] <noun>
Compound subjects consist of simple subjects joined by conjunctions.
<compound subject> = <simple subject> ("and" | "or") <simple subject> | "Either" <simple subject> "or" <simple subject> | "Neither" <simple subject> "nor" <simple subject>