What is Clause and Why Learn It?

We see words every day. We see sentences every day. They’re so concrete and visible.

In contrast, clauses sound so abstract. And why do we need them when we’ve words and sentences? We’ll explore the need for clause and much more in this post.

What’s a clause?

A clause is a group of words that has a subject doing something. Put simply, it’s a grammatical unit that contains a subject and a verb. If the group of words doesn’t have both, it becomes a phrase. It can be a complete idea (independent clause) or an incomplete idea (dependent clause). Examples (subject in blue font and verb in magenta):

whether he lied under oath

as if a lion was chasing him

that met with an accident last month and required major repair

he runs fast

Spotting a verb in clauses is much less challenging than spotting a subject. Here is a resource to help you in this regard:

The verb in a clause should be finite (or tense) verb

A finite verb has grammatical tense, and it corresponds to a subject in a sentence. A non-finite or non-tense verb (participle and infinitive), on the other hand, doesn’t have grammatical tense, and it doesn’t correspond to any subject in a sentence. Example: going and to go are non-finite verbs, but is going, was going, went, and has gone are finite verbs.

This group of words is a clause because it contains a finite verb (in magenta font), which corresponds to a subject (in blue font). Note that it also contains three non-finite verbs (underlined), but they don’t matter as far as determining a clause is concerned. What matters is presence of at least one finite verb and subject.

even though the court asked the police to submit status report giving details of investigation done so far in the case

This group of words, in contrast, is not a clause, even though it contains two non-finite verbs. That’s because it contains no finite verb.

after directing the police to not arrest the petitioner

Such group of words that contain only non-finite verb are also called non-finite clauses. The above group of words contains two non-finite clauses: after directing the police and to not arrest the petitioner. They’re, however, more popularly known as phrases, which are group of words without both subject and finite verb. Note that a regular clause is also called a finite clause to differentiate it from a non-finite clause.

More resources:

Why learn clause?

There are two ways to look at why we need clause.

1. Clause conveys complex information while functioning as a part of speech

Compare the two sentences (comments in square brackets).

The man came down quickly. [Adverb]

The man came down as if a lion was chasing him. [Adverb clause]

In the first sentence, an adverb quickly describes the manner in which the man came down. In the second, an adverb clause as if a lion was chasing him describes the manner in which the man came down. The adverb clause provides more details than the one-word adverb while functioning as an adverb. Another example:

My neighbor has a yellow car. [Adjective]

My neighbor has a car that met with an accident last month and required major repair. [Adjective (or relative) clause]

In the first sentence, the adjective yellow describes the noun car. In the second, the adjective clause, also called relative clause, that met with an accident last month and required major repair describes the noun car. But note how much more information does the clause convey while playing the same part of speech.

Clauses pack in lot more information than their word counterparts and are a must for expressing complex information concisely in sentences. You’ll find them in abundance in professional writing, this being an example with four dependent clauses.

And when I look at my granddaughters, who will very probably [live] to the end of the century, I wouldn’t like them to come to say that the planet is hell, and that I have not done enough to avoid it. The Washington Post

2. Clause brings structure to writing

A house can be constructed brick by brick. But what if larger prefabricated units, say portions of wall, are available to be assembled? That will save time as well as reduce the chance of error.

A sentence can be constructed word by word. But what if larger prefabricated units, say phrases and clauses, are available to be assembled? You get the point.

A sentence can be viewed as combination of the smallest unit (words) or a combination of words and larger units (phrases and clauses). For example, this sentence can be viewed as combination of words.

While the antelopes were drinking water, the crocodile leapt out of the river.

The same sentence can be viewed as combination of words, phrases, and clauses. (Phrases and clauses have been underlined, and they’ve been named in the same sequence in the comment. Note that single words have not been treated as phrases, though, when thinking in terms of phrases, it’s not uncommon to classify words as phrases.)

While the antelopes were drinking water, the crocodile leapt out of the river. [Noun phrase/Verb phrase/ Noun phrase/ Prepositional phrase]

While the antelopes were drinking water, the crocodile leapt out of the river. [Adverb clause/Independent clause]

Working with larger units of phrase and clause brings structure to writing and reduces errors compared to building things from scratch.

Clauses represent idea: dependent vs. independent clauses

Since subject and verb together essentially represent an idea – a person or thing (subject) doing (verb) something – a clause is essentially an idea. Such ideas are of two types: complete and incomplete. Incomplete ideas don’t convey a complete message. Example:

because he was ill

It’s an incomplete idea because we don’t know what happened because of illness. A complete idea, in contrast, conveys a complete message. Example:

Tom didn’t attend school yesterday.

Whereas a complete idea can stand as a sentence, an incomplete idea can’t. That’s why only one has period. Is the incomplete idea a waste, then? No, if it can be combined to a complete idea, it’ll make the idea more informative. Example:

Tom didn’t attend school yesterday because he was ill.

The incomplete idea gets life, and the sentence becomes more informative: symbiosis at play. The incomplete idea is called dependent clause because it is dependent on someone else for its survival. The complete idea is called independent clause because it can survive as a sentence on its own.

Tom didn’t attend school yesterday. [Independent clause]

because he was ill [Dependent clause]

Dependent clauses are of three types – noun clause, adjective (or relative) clause, and adverb clause – some of which we used in the examples earlier. Here is a pictorial representation of the entire clause family.

Types of clause

Note: Feel free to use the above image, using the link (url) of this post for reference/attribution.

We can add more prefab units to the above sentence to make it even more informative.

Tom, who is a straight-A student, didn’t attend school yesterday because he was ill. [Independent clause + Dependent clause + Dependent clause]

You can add a phrase too.

Tom, who is a straight-A student, didn’t attend school yesterday because he was ill, missing an important quiz. [Independent clause + Dependent clause + Dependent clause + Phrase]

See how prefab Lego-like structures came together to enrich the sentence. Joe Moran, in First you write a sentence, captures this when he says:

Only when you learn to separate clauses and phrases properly with commas can you write long sentences of lucidity and grace.

You can add more to make the above sentence even more informative, but of course you wouldn’t want to go beyond a point and make the sentence too bulky.

Based on what we’ve covered so far, here is an alternative definition of dependent clause:

A dependent clause is a prefabricated Lego-like unit containing both subject and verb. It conveys complex information concisely while functioning as one of the three parts of speech – noun, adjective, and adverb. The idea it carries though is not complete, and hence it can’t stand on its own as a sentence.

What’s the difference between a sentence and a clause?

A clause contains both subject and verb. So does a sentence.

What’s the difference between the two?

A sentence can exist with just one independent clause.

The hungry tiger attacked the bear.

But a sentence mostly contains multiple clauses, both dependent and independent. This, for example, contains two independent clauses.

The hungry tiger attacked the bear, but then it retreated.

And this contains two independent and two dependent clauses.

The hungry tiger, who last had a meal four days ago, attacked the bear, but then it retreated when the bear counter-attacked.

So, the relationship between sentence and clause can be approximated through this equation, with X and Y being number of independent and dependent clauses, respectively.

Sentence = X*(independent clause) + Y*(dependent clause)

If the sentence contains just one independent clause (X = 1 and Y = 0), the sentence and the independent clause are one and the same, like in the first example above. Or else, the sentence is a combination of the two types of clauses, like in the second and third examples above.

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How understanding of clauses helps your writing?

Most important, dependent clauses squeeze in complex information into independent clauses to form sentences that stand out, while making writing somewhat Lego-like. Since we’ve covered this earlier in the post, we’ll skip it here.

Understanding how dependent and independent clauses work help you subordinate less-important information to make your writing smoother. Let’s understand this through an example. We’ve following two pieces of information, which we want to combine into a sentence.

Travel & tourism suffered huge losses due to the pandemic. It contributes 10.4 percent to global GDP.

How do we do that? Here are two ways.

Travel & tourism suffered huge losses due to the pandemic, and it contributes 10.4 percent to global GDP.

Travel & tourism, which contributes 10.4 percent to global GDP, suffered huge losses due to the pandemic.

Which one would you prefer?

The first sentence gives equal emphasis to both the information, confusing readers as to which of the two is more important. Remember, when you join two independent clauses by a coordinating conjunction, both the clauses get equal importance.

In the second sentence, the less important information (contribution to global GDP) has been subordinated to the main information (losses due to pandemic) through a relative clause, thereby leaving no ambiguity and making reading smoother. In newspapers, non-fiction books, and other pieces of such writings, majority of sentences contain one independent clause, with multiple phrases and/or dependent clauses.

An implication of conveying one main idea in a sentence is that your next sentence builds on that idea. The above sentence, for example, should ideally continue like this.

Travel & tourism, which contributes 10.4 percent to global GDP, suffered huge losses due to the pandemic. Some fear that part of industry’s revenue from business travel may never come back as Zoom-culture is here to stay to some extent.

This wouldn’t be good as it builds on the subordinate idea.

Travel & tourism, which contributes 10.4 percent to global GDP, suffered huge losses due to the pandemic. According to a report, the industry’s contribution to global GDP plunged in 2020, leading to loss of more than 62 million jobs.

A sentence with two main ideas, however, can go in either direction.

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Anil Yadav

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