B. Foundations of Language · Foundations of Language: Listening, Speaking, Words, Fluency and Conventions

Building Complex Sentences: Clauses, Subordination and Combining Ideas Precisely

B3.1 B3.3 A3.1About 70 minutes

Learning goals

I can identify independent and dependent clauses, including adverb, adjective (relative) and noun clauses.
I can write simple, compound, complex and compound-complex sentences and punctuate them correctly.
I can choose which idea goes in the main clause to control emphasis.
I can combine short sentences so the relationship between ideas is accurate and clear.
I can explain how a writer's sentence structure affects meaning.

Words to know

independent clause
A group of words with a subject and a verb that can stand alone as a sentence: we lit candles.

dependent (subordinate) clause
A clause with a subject and verb that cannot stand alone; it depends on an independent clause: when the power went out.

subordination
Putting a less important idea in a dependent clause so the main idea stands out.

coordination
Joining ideas of equal importance with for, and, nor, but, or, yet, so.

relative clause
An adjective clause that begins with who, whom, whose, which or that and describes a noun.

noun clause
A dependent clause that acts as a noun: What she said surprised everyone.

compound-complex sentence
A sentence with at least two independent clauses and at least one dependent clause.

Remember from earlier grades

In Grade 7 you identified three kinds of dependent clauses (adjective, adverb and noun) and built complex sentences from phrases and clauses. In Grade 8 you chose subordinating conjunctions that show the precise relationship between ideas: cause (because), contrast (although), condition (unless), time (until). In Grade 9 you'll use these structures on purpose in analytical and persuasive writing, and you'll analyze how authors use sentence structure to create effects.

Let's start with three facts

The power went out. We lit candles. My brother told ghost stories.

Three short sentences, and the reader has to guess how they're related. Watch what combining does:

When the power went out, we lit candles, and my brother told ghost stories. (time, then two equal events)
Because the power went out, we lit candles, which gave my brother the perfect setting for ghost stories. (cause, then a result)

Each version shows a relationship between the ideas. Choosing the structure is choosing the meaning.

Clauses: the building blocks

A clause has a subject and a verb.

Independent clause: can stand alone: we lit candles.
Dependent clause: cannot stand alone. Three kinds:
Adverb clause (tells when, why, how, under what condition): when the power went out, because the road was icy, although it was late, unless it snows.
Adjective (relative) clause (describes a noun): the student who won the award, the novel that we read in October, Thunder Bay, which sits on Lake Superior.
Noun clause (does a noun's job, such as subject or object): What the coach said surprised us; I know that you tried your best; Nobody knew whether the bus would come.

Four sentence forms

Simple: one independent clause. The snow fell.
Compound: two or more independent clauses joined by a comma and a coordinating conjunction (for, and, nor, but, or, yet, so), or by a semicolon. The snow fell, and the schools closed.
Complex: one independent clause and at least one dependent clause. Because the snow fell all night, the schools closed.
Compound-complex: at least two independent clauses and at least one dependent clause. When the power went out, we lit candles, and my brother told ghost stories.

A compound-complex sentence. Notice the comma after the introductory dependent clause and the comma before and, which joins the two independent clauses.

Subordination controls emphasis

Readers give more weight to the independent (main) clause. Put your most important idea there and the background idea in the dependent clause.

Although the trip was expensive, it was worth it. → the message is worth it.
Although the trip was worth it, it was expensive. → the message is expensive.

Same facts, opposite emphasis. This matters in persuasive and analytical writing, where you want your claim in the main clause.

Switching which idea is in the main clause flips the message. Put your main point in the main clause.

Punctuation that goes with clauses

Introductory dependent clause → comma after it: When the bell rang, we lined up.
Dependent clause at the end → usually no comma: We lined up when the bell rang. (Exception: a contrast clause with although, though, whereas often takes a comma: She stayed calm, although she was nervous.)
Two independent clauses with a coordinating conjunction → comma before the conjunction: The snow fell, and the schools closed.
Relative clauses: commas only if the clause is extra (non-essential) information: My cousin, who lives in Iqaluit, is visiting. No commas if it identifies which one: The student who won the award spoke first.

Structure and effect in what you read

Writers choose structure for effect. A long complex sentence can pile up details and slow the reader down; a short simple sentence after it lands like a punch. When you analyze a text, ask: What's in the main clause? Why is this sentence so long, or so short?

Worked example

Let's combine sentences precisely

Combine into one sentence that shows the relationship accurately, with the community garden as the main point: The school had an empty courtyard. Students wanted fresh vegetables. They built a community garden. It now supplies the cafeteria.

Find the main point: students built a community garden. That goes in the main clause.
Find the relationships: the empty courtyard and the wish for vegetables are reasons (cause); supplies the cafeteria describes the garden (adjective clause).
Choose connectors: Because for cause; which for the extra information about the garden.
Build: Because the school had an empty courtyard and students wanted fresh vegetables, they built a community garden, which now supplies the cafeteria.
Check punctuation: comma after the introductory clause; comma before which (non-essential information).

Because the school had an empty courtyard and students wanted fresh vegetables, they built a community garden, which now supplies the cafeteria. (A complex sentence: main clause they built a community garden.)

Worked example

Let's analyze a writer's structure

An original short story includes: "The wind howled across the frozen lake, rattling the windows, tearing at the tarp on the woodpile, pushing snow under the door in thin white lines. Then it stopped." Explain how the sentence structure creates an effect.

First sentence: long, with one main clause (The wind howled across the frozen lake) and three -ing phrases piling up details.
Effect of the first sentence: the reader feels the storm going on and on; the list of actions builds tension.
Second sentence: very short, a simple sentence: Then it stopped.
Effect of the contrast: the sudden short sentence mirrors the sudden silence; it creates surprise and maybe unease.

The long first sentence piles up actions so the storm seems relentless; the abrupt simple sentence Then it stopped mirrors the sudden silence and creates suspense.

Intentional fragments

A fragment (a dependent clause or phrase punctuated as a sentence) is usually an error: Because the road was icy. But skilled writers sometimes use fragments on purpose for effect, especially in fiction and speeches: "Silence. Then footsteps." In formal essays, avoid them. In creative writing, use them rarely and deliberately.

Hands-on activity

Sentence surgery on your own writing

You need: a recent piece of your writing (any course), two highlighters or coloured pencils, and paper.

Highlight every independent clause in one colour and every dependent clause in another, in one paragraph.
Count your sentence forms: how many simple, compound, complex, compound-complex?
Find two places where short sentences could be combined to show a relationship (cause, contrast, time, condition). Rewrite them.
Find one long sentence and check that your main idea is in the main clause. If not, flip it.
Read the old and new paragraphs aloud to a family member. Which sounds more connected?

Just for fun

The shortest complete sentence in English is often said to be "Go." It's an imperative: the subject you is understood. It's also excellent advice for anyone who's been staring at a blank page for 20 minutes.

Your turn

Identify the dependent clause and its type: The novel that we read in October was set in Saskatchewan.

Identify the sentence form: Although it was minus 20, the team practised outside, and nobody complained.

Identify the noun clause and its job: What the scientist discovered changed the study.

Combine with subordination to show cause: The ferry was cancelled. We stayed another night.

Rewrite so the main point is that the movie was boring: The movie had great special effects. It was boring.

Add the missing commas: When the bus finally arrived we climbed aboard and the driver smiled.

Is this a fragment or a sentence? Which surprised everyone. Fix it.

More practice: warm-up

What two things does every clause have?

Name the seven coordinating conjunctions.

Give two subordinating conjunctions that show contrast.

Which form is this? The snow fell.

Which relative pronoun is used for people: who or which?

More practice: on your own

Combine into one complex sentence using a relative clause: Dr. Singh will speak at the assembly. She studies polar bears.

Explain the difference in meaning: (a) The students who finished early went outside. (b) The students, who finished early, went outside.

Combine to show condition: You submit the form by Friday. You can join the trip.

Write a compound-complex sentence about winter, and label its clauses.

Explain why this combination is inaccurate: Because the team trained hard, they lost the final. Fix it.

Challenge

Rewrite this paragraph to improve flow and show relationships, using at least one complex and one compound-complex sentence: The town grew. More people needed homes. Developers built on farmland. Some residents were upset. They wanted to protect the land.

A persuasive essay says: "Although the new arena would bring jobs, it would destroy a wetland." What is the writer's position, and how does the structure show it?

Write two sentences about the same event: one long sentence with a series of details, followed by a short simple sentence. Explain the effect.

Check your understanding

Quiz

Which is a dependent clause?

Although it rained, we played, and we won. This sentence is:

In What she said surprised everyone, the clause What she said is:

Which sentence emphasizes that the hike was worth it?

Where does the comma go? When the bell rang we lined up.

Which combination shows the relationship accurately? (The road was icy. We drove slowly.)

For parents and teachers

Big idea: B3.1 asks students to use their knowledge of sentence types and forms to construct complex sentences that connect and communicate ideas accurately and effectively.

How to help at home: When your teen writes, ask, "What's the most important idea in this sentence? Is it in the main clause?" and "How are these two sentences related: cause, contrast, time?"

Common difficulties:

Wrong connector (because where although is meant).
Fragments that are dependent clauses on their own (Which was surprising.).
Commas: missing after introductory clauses, or around essential relative clauses where they don't belong.
Overlong sentences. Complex doesn't mean as long as possible; it means accurately connected.