What makes a sentence a sentence? Is it the morphemes, the phrases, or the clauses? The answer is all of the above! The above elements come together to form constituents, which are the units of language that work together to create complete sentences.
Having a good understanding of constituents is an essential first step in your studies of syntax. Today we'll be learning about constituent types and structures, constituent identification, such as parsing, and different tests you can conduct to help you decide which group of words are and are not constituents.
Constituent Linguistics
Within linguistics, a constituent is a unit of language that exists within a larger sentence. Constituents are a vital part of syntax, and each constituent must follow the general rules of syntax. When we analyze the syntax of a sentence, we conduct a process called parsing, which involves breaking a sentence down into its constituents.
Fig 1. An example of parsing.
Every sentence contains constituents - they are the essential building blocks that make a sentence a sentence. Let's now take a closer look at the definition of constituent.
Constituent Definition
Constituents are the units of language that work together to build a sentence. They can be morphemes, phrases, and clauses (we'll look at examples of each of these shortly).
The vital constituents within a sentence are the subject and its predicate. A subject is who/what the sentence is about, and a predicate is the part of a sentence that adds detail or information to the subject (they usually contain a verb.)
"The man with the old brown shoes is the manager."
In this example, we can see two constituents: the subject (The man with the old brown shoes) and its predicate (is the manager).
Larger constituents can be further broken down into their own constituents.
The constituent "The man with the old brown shoes" is a noun phrase that also contains the preposition phrase constituent "with the old brown shoes"
This means that each sentence can contain multiple different constituents.
There are several 'tests' to help identify which phrases are constituents within a sentence. One example is testing which units of language can be replaced with a singular word.
"The man with the old brown shoes is the manager."
"He is the manager"
In the above example, we can see that the noun phrase "The man with the old brown shoes" is a constituent, as all seven words can be replaced with the singular word he. We'll cover constituency tests in more detail later.
Constituent Types
As we mentioned, constituents can be morphemes, phrases, or clauses. The smaller constituents (e.g., morphemes) combine to form larger constituents (e.g., phrases), which can again combine to form larger constituents (e.g., clauses or predicates). Let's look at each of these with some examples.
Morphemes
Morphemes are the smallest unit of lexical units; they can be free (can stand alone) or bound (cannot stand alone). In simple terms, free morphemes are individual words that cannot be broken down further (e.g., cat, he, laptop, etc.), and bound morphemes are the affixes we attach to them (e.g., quickly, unfinished, houses, etc.).
Here, the free morpheme 'he' is the subject of the sentence and a valid constituent.
As bound morphemes cannot stand alone, they cannot be constituents on their own.
Phrases
Phrases are constituents that contain a group of words that act as a particular word class, i.e., a noun phrase works as a noun. Phrases can be categorized into noun phrases, verb phrases, prepositional phrases, adverb phrases, and adjective phrases.
"It was a very big cake."
"a very big cake" is the noun phrase. The phrase contains the main noun plus all the words that modify it.
"very big" is an adjective phrase within the noun phrase.
They are both constituents within the sentence.
Clauses
A clause is a constituent that contains a subject and a predicate. There are two types of clauses: independent and dependent. Independent clauses can stand alone, whereas dependent classes must be connected to independent clauses to get their meaning.
"Because he was hungry, Iain went to get pizza."
In this example, we can see two separate clause constituents: the dependent clause (because he was hungry) and the independent clause (Iain went to get pizza).
Now we have a good understanding of the elements of constituents, let's take a closer look at how they are structured.
Constituent Structure
The term constituent structure describes the grammatical structure of a sentence and how smaller constituents combine to form larger constituents.
For example, morphemes combine to form phrases, and phrases combine to form additional phrases and clauses. Additionally, each sentence will typically contain two main constituents: the subject and the predicate. Subjects are often nouns or noun phrases, and predicates are often verb phrases; however, this isn't always the case.
It is possible to get sentences without a subject or verb. This is because the subject or verb is either ellipted or implied, i.e., physically removed from the sentence but still understood as being there. For example, "You watch out!"
Immediate Constituent Analysis
The simplest way to illustrate constituent structure is by conducting an Immediate Constituent Analysis (aka IC analysis). Immediate Constituent Analysis is a form of parsing, a technique that involves breaking a sentence down into its constituents and presenting them in a tree diagram, like so:
Fig 2. Constituent Structure
When studying syntax, you will come across many tree diagrams. We use constituency tests to prove the existence of each constituent in a sentence. Read on to find out more about constituency tests.
Constituent Identification
Now we know all about constituents and their structure, let's look at some useful ways of identifying constituents within a sentence. One useful way to identify constituents is by conducting 'tests' (remember how at the beginning of the article we tried replacing whole phrases with a singular word? This was an example of a constituency test!)
Let's look at some more tests now.
Constituency Tests in Syntax
Formal constituency tests involve manipulating sentences, i.e., playing around with their order, to discover which groups of words are constituents. It's important to note that some tests work better for some sentences than others.
Sentence Fragment Answers
To conduct a sentence fragment test, restructure the sentence to form a question and an answer. Only constituents can be an appropriate answer while maintaining the same meaning.
Constituents are in bold. Non-constituents are underlined.
"This is my cat."
Q: Whose cat is this?
A: my cat
"The food is in the fridge."
Q. Where is the food?
A: in the fridge
"I want six of those cakes."
Q: What do you want?
A: six of
Pro-form Substitution
The pro-form substitution test is the first test we saw in this article - it involves replacing a group of words with a pro-form word. If the words can successfully be replaced, they are a constituent.
Pro-form words - A word that can take the place of another word or phrase, e.g., a pronoun.
"The man with the beard is my brother."
=
"He is my brother."
"She went away to the mountains."
=
"She went there."
Coordination
Only constituents can be joined to other constituents of the same kind (i.e., a noun phrase and a noun phrase) with the use of coordinating conjunctions. The coordinating conjunctions are For, And, Nor, But, Or, Yet, So,
"We mashed the potatoes."
=
"We mashed the potatoes (and peeled the carrots)." (verb phrase + verb phrase)
Topicalization
The topicalization test involves moving the potential constituent to the beginning of the sentence and seeing if it still makes sense.
"We're visiting our grandparents over the break."
=
"Over the break, we're visiting our grandparents."
"We're going skiing over the weekend."
=
"skiing over, going the weekend."
Clefting
Clefting involves placing the constituent within a frame and seeing if it still makes sense.
The frame is, "___ is/are + who/what/where/when/why/how."
"We put the shoes in the bag."
=
"In the bag is where we put the shoes."
"She was incredibly beautiful."
=
"Incredibly beautiful is what she was."
"They made us pizzas."
=
"Made us is what they pizza."
It's important to remember that the same group of words may function as a constituent in one sentence but not in another. Syntax isn't just about the order of words, it's about the relationship between those words and the role they play within the sentence.
Constituent Example
It's time to put all of our new knowledge together. Let's take an example sentence and identify all of its constituents by conducting an Immediate Constituent Analysis and Sentence Fragment Answer and Topicalization tests.
Sentence = "The retired man grew potatoes in his garden."
First, identify the subject and the predicate - remember, subjects are usually noun phrases, and predicates are often verb phrases.
Noun phrase (subject) = The retired man
Main verb phrase (predicate) = grew potatoes in his garden
Verb phrase = grew potatoes
Prepositional phrase = in his garden
Let's now try a Sentence Fragment Answer test to see if we have grouped the correct words together into constituents.
Q: What did the retired man do?
A: Grew potatoes
Q: Where did the returned man grow potatoes?
A: in his garden
We can also apply the Topicalization test:
"The retired man grew potatoes in his garden."
"In his garden, the retired man grew potatoes."
Constituents - Key takeaways
- A constituent is a syntactical unit of language that exists within a larger sentence.
- When we analyze the syntax of a sentence, we conduct a process called parsing, which involves breaking a sentence down into its constituents.
- The vital constituents within a sentence are the subject and its predicate. Subjects are usually noun phrases, whereas predicates are often verb phrases.
- Constituents can be morphemes, phrases, or clauses. The smaller constituents (e.g., morphemes) combine to form larger constituents (e.g., phrases), which can again combine to form larger constituents (e.g., larger phrases or clauses).
- Constituency tests involve manipulating sentences, i.e., playing around with their order, to discover which groups of words are constituents. Tests include: substitution, coordination, clefting, and sentence fragment answers.
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