Advanced English Fluency
Complex Sentence Structures
Beyond the Basics
Simple sentences get the job done, but to express more complex ideas, you need more sophisticated tools. The key is learning how to connect ideas using clauses. A clause is a group of words with a subject and a verb. The ones we'll focus on are dependent clauses—they can't stand alone as a full sentence but add crucial information to the main part of your sentence.
Think of a main clause as a complete story and a dependent clause as a fascinating side note that adds depth and context.
Types of Dependent Clauses
Dependent clauses come in three main flavors, each serving a different grammatical role. They can act like adjectives, adverbs, or nouns.
Relative Clauses
These clauses act like adjectives, which means they modify nouns or pronouns. They often begin with relative pronouns like who, whom, whose, which, or that.
A relative clause immediately follows the noun it's describing, giving us more information about it.
Instead of saying: "The dog is friendly. It lives next door."
You can say: "The dog that lives next door is friendly."
The clause "that lives next door" tells us more about "the dog."
Adverbial Clauses
Just as adverbs modify verbs, adverbial clauses do the same job. They answer questions like when?, where?, why?, how?, or under what conditions? They are connected to the main clause with a subordinating conjunction.
| Question Answered | Common Conjunctions |
|---|---|
| When? (Time) | after, before, when, while, since, until |
| Why? (Cause) | because, since, as |
| Under what condition? | if, unless, provided that |
| Despite what? (Concession) | although, though, even though |
| Where? (Place) | where, wherever |
For example, in the sentence, "Because it was raining, we stayed inside," the adverbial clause tells us why we stayed inside.
Noun Clauses
These clauses function as nouns. That means they can be the subject of a sentence, the object of a verb, or the object of a preposition. They often start with words like that, what, whoever, why, and how.
As a subject: "What she said surprised me."
As an object: "I don't know why he left."
In both cases, the entire clause acts as a single noun.
Connecting with Commas
Punctuation is crucial for clarity in complex sentences. The most common question involves when to use a comma.
When an adverbial clause comes before the main clause, separate them with a comma.
- Correct: When the movie ended, we went home.
If the adverbial clause comes after the main clause, you usually don't need a comma.
- Correct: We went home when the movie ended.
For relative clauses, commas depend on whether the clause is essential to the sentence's meaning. If the information is just extra, set it off with commas. This is called a non-restrictive clause.
If the information is necessary to identify which noun you're talking about, don't use commas. This is a restrictive clause.
Non-restrictive (extra info): My brother, who lives in Miami, is a doctor. (I only have one brother, and I'm just adding a detail.)
Restrictive (essential info): My brother who lives in Miami is a doctor. (I have more than one brother, and I'm specifying which one.)
Now, let's test your understanding of these structures.
In the sentence, 'The book that is on the table belongs to me,' what type of clause is 'that is on the table?'
Which of these sentences uses a comma correctly with an adverbial clause?
Mastering these clauses and their punctuation will allow you to express sophisticated ideas clearly and effectively.