Complex Sentences for intermediate learners

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A complex sentence is a sentence that contains an independent clause and one or more dependent clauses. In this lesson, we will learn all about this type!

intermediate advanced

"Complex Sentences" in the English Grammar

What Are Complex Sentences?

A complex sentence consists of one independent clause along with one or more dependent clauses.

Dependent Vs. Independent Clause

As you may know, dependent clauses cannot be used alone because they rely on other clauses to become complete, while independent clauses are complete and meaningful on their own. Compare the following examples:

I have three cats and a dog.

Here, we have an independent clause.

When you came into my room...

As you can see, the sentence has a subject and a verb, but it is not complete.

Complex Sentences: Uses

We can use complex sentences to join independent and dependent clauses together. This helps us write more fluently. Take a look at the following examples:

When she came into my room, she looked like she had just run from hell.

If Anna keeps talking, I swear to God I will kill her.

Tip!

We can change the places of the dependent and the independent clauses in complex sentences. Take a look at the examples below:

I was angry because of all the lies you had told me.

Because of all the lies you had told me, I was angry.

Identifying Complex Sentences

In order to identify a complex sentence, we can search for subordinating conjunctions. They are markers used to connect dependent clauses to independent ones. Some of the most commonly-used subordinating conjunctions in English are When, If, Since, and Although.

Now, let us see some examples:

If you go back to him, you will get hurt again.

As you can see, the dependent clause has been used with 'if'.

Since you didn't come to the party, you are not allowed to ask questions about it.

When Bill rejected her calls, she became really anxious.

Punctuation Rules

The only punctuation rule we need to apply to complex sentences is to use a comma between the clauses when the dependent clause comes first. Compare the following sentences:

When you came into our room, you looked terrible.

You looked terrible when you came into our room.

Complex vs. Compound Sentences

The only difference between complex and compound sentences is that compound sentences join two independent clauses together, while a complex sentence must have at least one dependent clause. Compare the following examples carefully:

That coffee is brewed and this one is decaf.

Here, this is a compound sentence because each clause is independent.

You can talk to me if you want.

As you can see , this is a complex sentence and we have a dependent clause.