Subjects are words, phrases, and clauses that perform the action of or act upon the verb. Although nouns, pronouns, and noun phrases most frequently function as the subjects of sentences, four grammatical forms can perform the grammatical function of subject in the English language. The four grammatical forms that can function as the subject are:
Noun Phrases as Subjects
The first grammatical form that performs the grammatical function of subject is the noun phrase. Noun phrases are defined as phrases that consist of a noun or pronoun plus any modifiers, complements, and determiners. For example, the following the following italicized noun phrases function as subjects:
- Cats primarily eat meat.
- My cat also likes to eat popcorn.
- I feed my cat wet and dry cat food.
- That fat cat needs more exercise.
- Her mother-in-law’s cat behaves strangely.
- The mother of my kitten must have been a stray.
Noun phrases are the most frequent grammatical form that function as the subject in the English language.
Noun Clauses as Subjects
The second grammatical form that can perform the grammatical function of subject is the noun clause. A noun clause is defined as a subordinate clause that consists of a subordinating conjunction followed by a clause and that performs a nominal function. For example, the following italicized noun clauses function as subjects:
- That he lied shocked me.
- What the teacher said confused the class.
- Whomever you invite is fine with me.
- That prepositional phrases and verb phrases can function as subjects is surprising.
- Whether a noun phrase is a subject or object in English depends on word order.
- What you previously thought about grammatical subjects was incorrect.
Verb Phrases as Subjects
The third grammatical form that can perform the grammatical function of subject is the verb phrase in the form of present participles and infinitives. Verb phrases are defined as phrases that consist of a verb plus any modifiers, complements, particles, infinitive markers, or other verbs. For example, the following italicized verb phrases function as subjects:
- Reading is fun.
- Drinking milk is healthy.
- My drinking milk pleases my mother.
- To err is human.
- To forgive is divine.
- To become a librarian requires at least one graduate degree.
Traditional grammars typically refer to present participles functioning as subjects as gerunds.
Prepositional Phrases as Subjects
The fourth grammatical form that can perform the grammatical function of subject is the prepositional phrase. Prepositional phrases are defined as phrases that consist of a preposition directly followed by a word, phrase, or clause that functions as a prepositional complement. For example, the following italicized prepositional phrases function as subjects:
- In the closest is dark.
- Behind the garage is a muddy mess.
- Under the bed needs cleaning.
- Above the freezer needs dusted.
- After six is a good time to call.
- Between seven and nine is when employees must arrive.
Prepositional phrases that function as subjects generally refer to locations and times.
The four grammatical forms that can function as the subject in the English language are noun phrases, noun clauses, verb phrases, and prepositional phrases.
Brinton, Laurel J. & Donna M. Brinton. 2010. The linguistic structure of Modern English, 2nd edn. Amsterdam: John Benjamins Publishing Company.
Hopper, Paul J. 1999. A short course in grammar. New York: W. W. Norton & Company.
Huddleston, Rodney. Introduction to the Grammar of English. Cambridge University Press: Cambridge, 1984.