B. Foundations of Language · Foundations: Grammar, Sentences and Punctuation

Sentence Types and Forms: Choosing the Right Sentence

B3.1 B3.3About 40 minutes

Learning goals

I can name the four sentence types (by purpose) and the four sentence forms (by structure).
I can tell a phrase from a clause, and an independent clause from a dependent clause.
I can use the right end punctuation and capital letters for each sentence type.
I can choose sentence types and forms on purpose to make my writing clear and interesting.

Words to know

sentence type
What a sentence does: tells (declarative), asks (interrogative), commands or requests (imperative) or shows strong feeling (exclamatory).

sentence form
How a sentence is built: simple, compound, complex or compound-complex.

clause
A group of words with a subject and a verb.

independent clause
A clause that can stand alone as a sentence. Also called a main clause.

dependent clause
A clause that cannot stand alone. It usually starts with a word like because, when, although, who or that. Also called a subordinate clause.

phrase
A group of words that works together but does not have a subject-and-verb pair, like under the bridge or to catch the bus.

Welcome to Grade 7 grammar!

Read these two notes from a coach.

Note A: Practice is cancelled. The arena roof is leaking. We will practise Thursday. Bring your skates.

Note B: Practice is cancelled because the arena roof is leaking. Can everyone come on Thursday instead? Bring your skates!

Both notes give the same facts. Note B sounds friendlier and shows how the ideas connect (the roof leak is the reason). The difference is the sentences the coach chose. In this unit you will learn to build sentences on purpose, like an engineer builds a bridge.

Remember from earlier grades

In Grade 4 you learned the four sentence types. In Grade 5 you built compound-complex sentences and fixed fragments, run-ons and comma splices. In Grade 6 you built complex sentences with adjective (relative) clauses and combined sentences to show how ideas are related.

Grade 7 puts it all together: you will combine phrases and clauses to show exactly how your ideas relate, learn new jobs that words do in sentences, and use new punctuation tools: semicolons, colons before quotations, ellipses and dashes.

Sentence type	Its job	End mark	Example
Declarative	Tells or states	. (period)	The library opens at ten.
Interrogative	Asks	? (question mark)	Is the library open today?
Imperative	Commands or requests	. or !	Please return your books.
Exclamatory	Shows strong feeling	! (exclamation mark)	What a huge library this is!

The four sentence TYPES are about purpose. Every sentence starts with a capital letter.

Each sentence type has its own job, and the job decides the end mark. An imperative usually ends with a period, but a strong command can end with an exclamation mark.

Clauses and phrases

A clause has a subject and a verb. A phrase does not.

the dog barked → clause (subject dog, verb barked)
because the dog barked → still a clause, but a dependent one. It can't stand alone.
across the frozen field → phrase (no subject-and-verb pair)

An independent clause can stand alone as a sentence. A dependent clause needs an independent clause to lean on.

The four sentence forms

Simple: one independent clause. The snow fell.
Compound: two or more independent clauses joined by a comma and a joining word (for, and, nor, but, or, yet, so), or by a semicolon. The snow fell, and the roads closed.
Complex: one independent clause and at least one dependent clause. When the snow fell, the roads closed.
Compound-complex: at least two independent clauses and at least one dependent clause. When the snow fell, the roads closed, and the buses stayed home.

Sentence forms as building blocks. IC (green) = independent clause. DC (yellow) = dependent clause. A dependent clause can also come after the independent clause.

Worked example

Let's name a sentence's type and form

What type and form is this sentence? Because the Blue Jays won, my cousin cheered all evening, and we ate popcorn.

Type: it tells us something and ends with a period, so it is declarative.
Find each subject-and-verb pair: the Blue Jays won, my cousin cheered, we ate. That's three clauses.
Because the Blue Jays won starts with because and can't stand alone, so it is dependent.
my cousin cheered all evening and we ate popcorn can each stand alone, so they are independent.
Two independent clauses + one dependent clause = compound-complex.

A declarative, compound-complex sentence.

Worked example

Let's improve a choppy paragraph

Rewrite using different forms: We went to the sugar bush. It was March. The sap was running. We tasted maple taffy on snow. It was delicious.

Five simple sentences in a row sound choppy. Look for ideas that connect.
It was March tells when. Turn it into a phrase: In March.
The sap was running explains why it was a good time. Make it a dependent clause: because the sap was running.
Keep the tasting as a short simple sentence, and turn It was delicious into an exclamatory sentence to show the feeling.

In March, we went to the sugar bush because the sap was running. We tasted maple taffy on snow. How delicious it was! Now there is a complex sentence, a simple sentence for a clear moment, and an exclamation for feeling.

Short sentences have power

Don't make every sentence long! A short simple sentence after a few long ones grabs attention: We searched the whole park, the school yard and every street in the neighbourhood for our lost dog. Then we heard a bark. Good writers mix forms on purpose.

Just for fun

One of the shortest complete sentences in English is just one word: Go. It is an imperative, and its subject, you, is hiding in plain sight!

Hands-on activity

Sentence form scavenger hunt

You need: three different texts from home (for example, a novel, a cereal box or recipe, and a news article or flyer), sticky notes or scrap paper, and a pencil.

In each text, find one example of each sentence form: simple, compound, complex and compound-complex. Copy each one onto a sticky note.
Label each clause: draw a box around independent clauses and underline dependent clauses.
Now find one sentence of each type (declarative, interrogative, imperative, exclamatory). Which text has the most imperatives? (Recipes usually do. Why?)
Talk with a grown-up: Which text uses the most long sentences? Which uses short ones? Why do you think the writer chose them?

What to look for: a recipe is mostly imperative (Stir the batter.) because it gives instructions; a novel mixes all four forms to control pace and feeling.

Your turn

Name the type and form: Close the door before the cat gets out.

Name the type and form: What a beautiful sunset that is!

Name the type and form: Did you finish your science lab, or do you need more time?

Name the type and form: The maple leaves turned red in October.

Name the form: When the bell rang, the students who had finished left quietly, but Omar stayed.

Phrase or clause? under the frozen pond

Phrase or clause? since the ice melted

More practice: warm-up

What type of sentence is Please pass the salt, and what end mark does it need?

Add the end mark: Is the library open on Sundays

What type is Our class collected 200 cans for the food bank.?

Simple or compound? Lina skated, and her brother played hockey.

Independent or dependent? although it was snowing

More practice: on your own

Combine into a compound sentence: The wind was cold. We finished the hike.

Combine into a complex sentence: The power went out. We played board games by flashlight.

Name the form: The students who volunteered at the food bank received a thank-you letter.

Change into an interrogative sentence: The bus arrives at 8:15.

Why might a writer put a short simple sentence right after several long ones?

Challenge

Write a compound-complex sentence about winter. Label the clauses.

Find and fix the error: Although we practised every day. We lost the final game.

Rewrite You should wear a helmet when you ride your bike. as (a) an imperative and (b) an interrogative sentence.

Check your understanding

Quiz

Which sentence is interrogative?

Which group of words is a phrase?

What form is this sentence? We wanted to go swimming, but the pool was closed.

What form is this sentence? If it snows tonight, we will build a fort.

Which is a dependent clause?

Which is the best reason to use a short simple sentence in a story?

For parents and teachers

What this lesson is about: naming sentences by purpose (type) and by structure (form), and choosing them on purpose. Most of this is review from Grades 4 to 6, which sets up the new Grade 7 work.

How to help at home:

When your child reads aloud, stop at an interesting sentence and ask: "How many subject-and-verb pairs are there? Which part could stand alone?"
Look at a recipe, a flyer and a novel together and compare their sentences.
Ask your child to read their writing aloud and listen for choppy strings of short sentences or very long ones that run on.

Common difficulties:

Imperative sentences seem to have no subject. The subject you is understood: (You) close the door.
Thinking every long sentence is compound-complex. Count clauses, not words.
Treating a dependent clause (Because I was tired.) as a full sentence. This is a fragment.