What is a dependent clause? All you need to know about dependent clauses

An English clause consists of a subject and a verb inflected for tense. There are two types of clauses: independent clauses and dependent clauses. A dependent clause also plays an important role when combined with an independent clause to form a complex sentence. So what is a dependent clause? How many types of dependent clauses are there? Let's explore dependent clauses and their usage together on PREP in the following article.

I. Dependent clause definition

Dependent and independent clauses are 2 main types of clauses that form a sentence. To differentiate between independent and dependent clauses, let’s join PREP to discover the definition as well as the usage of dependent clauses.

A dependent clause is a group of words formed by a subordinator, a subject, and a predicate that complements the sentence. This type of clause cannot stand alone as it does not express a complete idea. As such, a dependent clause needs to be combined with another independent clause to form a complete sentence.

When a dependent clause is combined with an independent clause, it forms a complex sentence. Below are some dependent clause examples to help illustrate their structure and usage:

• Even though I didn’t bring an umbrella, I still walked to the park. ➡ In this example, “Even though I didn’t bring an umbrella” is a dependent clause. If used alone, a dependent clause would not make sense by itself. However, when placed within a full sentence, it plays an important role of providing context or additional information to the main clause: “I still walked to the park.” .
• When I met my old friend, I was really happy and invited her to my party. ➡ The independent clause “When I met my old friend” in this sentence adds additional information to the clause “I was really happy and invited her to my party.”

II. The usage and types of dependent clauses in English

1. Adverbial clause

Adverbial clauses typically serve an adverbial function, meaning they can modify verbs, adjectives or other adverbs. Some common types of adverbial clauses include:

• Time clause (dependent clause that indicates time): start with When, While, as, until,…
• Concessive clause (dependent clause that indicates concession): start with Although, Though, Even though, in spite of, despite…
• Purpose clause (dependent clause that indicates purpose): start with in order to, so as to hoặc so that, in order that…
• Causal clause (dependent clause that indicates causes): start with because, as, since, seeing that, due to the fact that, now that…

Examples: 

• After the girl received a phone call from her friend, she left home immediately. ➡ The adverbial clause comes before the main clause and modifies the information to the main verb “left”.
• The baby is cute when he is young. ➡ The adverbial clause comes after the main clause and modifies the information to the adjective “cute”.

Note: When an adverbial clause comes before an independent clause, you need to use a comma (,) to separate them; conversely, if the adverbial clause comes after, you don't need to use a comma.

2.  Nominal clause

The nominal clause is one type among the dependent clauses and serves as a noun. Therefore, this clause often starts with "that, how, who, whoever, whom, whomever, whose, what, whatever, which, whichever, where, when, why, whether, or if.

Examples:

• What I read in that book made me unable to forget. ➡ In this example, the clause “What I read in that book” acts as the subject at the beginning of a sentence and is a noun phrase.
• America is where I want to come to study. ➡ The dependent clause “where I want to come to study” comes after a tobe, a noun or a predicate, adds meaning to the subject as well as to redefine the subject's object after the linking verb (the 'to-be' verb)

3. Adjectival clause 

Adjectival or relative clauses function similar to adjectives by describing nouns or pronouns. To begin an adjectival clause, we can use relative pronouns like who, whom, whose, which, what or that, or relative adverbs such as when, why or where. The adjectival clause will follow the noun or pronoun it modifies.

Example:

• Staff who didn’t attend the conference need to do so tomorrow. ➡ The adjectival clause “who didn’t attend the conference” modifies the information to “Staff”.
• The students who complete the assignment early can leave class early. ➡ The adjectival clause "who complet the assignment early" modifies the information to "students".

III. How to build a complex sentence with dependent clauses and an independent clause

A complex sentence is formed with one independent clause with one or more dependent clauses using subordinators (when, while, because, although, since, unless, etc.) or relative pronouns (who, whom, which, that).

The general formula:

Independent clause + >= 1 dependent clause(s) 

In theory, we can construct a simple complex sentence with 1 independent clause + 1 dependent clause, or a more complex compound sentence with multiple dependent clauses.

We can flexibly change the positions of the independent and dependent clauses within a complex sentence. Below are some positions of the two clauses within a complex sentence:

• Position 1: Independent clause first, followed by the dependent clause.
• Position 2: Dependent clause first, followed by the independent clause.
• Position 3: Independent clause between two dependent clauses.
• Position 4: Two dependent clauses together, followed by the independent clause (or vice versa).

Examples: 

• When I bought my son a shirt for his birthday, I picked a red one because that’s his favorite color. ➡ In this example, the dependent clause “When I bought my son a shirt for his birthday” comes before the independent clause “I picked a red one because that’s his favorite color.”
• I heated my coffee in the microwave because it was too cold. ➡ In this example, the independent clause “I heated my coffee in the microwave” comes before the dependent clause “because it was too cold”.

IV. How to build a compound-complex sentence with dependent clauses and independent clauses

A sentence that combines at least two independent clauses with at least one dependent clause forms a compound-complex sentence.

The general formula:

>= 2 independent clauses + >= 1 dependent clause 

Examples: 

• Safety is one of the most commonly mentioned reasons; indeed research from the UK’s Transport Research Laboratory has shown that more than 90% of road incidents include human error as a contributing element, and in the great majority of cases, it is the primary cause. ➡ The example above includes 3 independent clauses and 1 dependent clause. Therefore, this is a compound - complex sentence.
• I couldn’t help him because I didn’t know the situation, but if he returns, you should help him. ➡ This sentence contains 2 independent clauses and 2 dependent clauses, so it's a compound-complex sentence.

V. Exercises on dependent clauses in English

To memorize dependent clauses’ usage and categorization, let’s practice by the following exercise on dependent and independent clauses.

Exercise: Identify the dependent clauses in the following sentences

• When I lived in this village, we often played football.
• My husband gave food to poor people whom he met on the street.
• Because the boy was smart, he absorbed the lesson very quickly.
• If he kept lying, no one would believe him.
• I’m about to go to a place that I’ve been dreaming of.

Keys:

• Dependent clause: When I lived in this village.
• Dependent clause: whom he met on the street.
• Dependent clause: Because the boy was smart
• Dependent clause: If he kept lying.
• Dependent clause: that I’ve been dreaming of.

The information mentioned above is what PREP aims to share about dependent clauses. Besides, you may refer to other common structures to have a solid foundation for learning and communication.