COMPOUND SENTENCES

This lesson explains how coordinating conjunctions create compound sentences.

All IELTS essays will use the conjunctions shown below. Examiners pay particular attention to conjunctions (which help them give a grade for both Grammatical Range and Accuracy, and Coherence and Cohesion.

Therefore, the more you understand and practice using conjunctions to create different sentence types, the better.

What is a conjunction?

Conjunctions are words used to connect ideas. Their purpose is to join clauses, sentences or idea within a clause, but for this lesson we will concentrate on joining clauses. 

There are two types of conjunctions known as coordinating and subordinating conjunctions. Knowing the difference between these types (and mastering their usage) is necessary for high IELTS grades. This lesson will focus on coordinating conjunctions and the compound sentences they create.

Coordinating conjunctions 

The word ‘coordinating’ means ‘matching’ and in grammar it means matching something that is grammatically equal. 

The conjunctions used to match these ‘equals’ are: 

For - And - Nor - But - Or - Yet - So  (FANBOYS)

Coordinating conjunctions can be used to join nouns, verbs, adjectives or adverbs, phrases or independent clauses (but not dependent clauses).

Compound sentences

Compound sentences join two independent clauses using a coordinating conjunction (as shown above) or a semi-colon (but that will be explained later).

Read the example sentence below that uses the coordinating conjunction ‘and’. Is this a simple sentence or a compound sentence?

Example 1a - The little girl asked for a cat and a dog.

In this sentence, the conjunction ‘and’ joins two equally important nouns. Coordinating conjunctions can be used to join nouns, verbs, adjectives or adverbs. This is a simple sentence because it contains only one independent clause (there is only one subject and one verb).

Example 1a is not a compound sentence because ‘and’ does not join two independent clauses. To be a compound sentences Example 1a must be re-written as follows:

Example 1b - The little girl asked for a cat, and she asked for a dog.

In this example, ‘and’ joins two clauses that contain a subject (the little girl/she) and a verb (asked/asked). It is now a compound sentence. In this sentence type, a comma is required before the conjunction to show the separation of the clauses.

Although both of the previous examples are grammatically correct 1a is usually preferred. After all, the English language tends to avoid unnecessary repetition. 

In Example 2a below, the two independent clauses contain a different verb. In this case it is common to use a coordinating conjunction. Again, a comma is required because both clauses contain a subject and a verb.

Example 2a - The man stood up, but he didn’t see anything.

However, once again there is repetition. This time the subject is repeated even though a pronoun is used (the man/he). Therefore, it is possible to shorten the sentence to:

Example 2b - The man stood up but didn’t see anything.

Example 2b is no longer a compound sentence because there is only one independent clause. In fact, this is known as a compound predicate, which is useful to know in IELTS for just one reason: commas.

Commas

In a compound sentence, a comma must be placed before the coordinating conjunction.

If the coordinating conjunction is not in a compound sentence (e.g. a compound predicate), no comma is required. 

These examples show the correct usage of commas:

1. The patient was feeling very sick, so the doctor called an ambulance.

2. The patient arrived at the hospital quickly, but all the doctors were busy.

3. The patient felt sick and wanted to leave.

4. There were five patients in the hospital, but only four had the virus.

5. The virus caused a fever but no other symptoms.

6. The doctor was worried, so he ordered more tests.

7. The patient was not able to speak, nor was she breathing normally.

8. The doctor told the nurse to give medicine and take a temperature recording.

9. There was a loud bang, so the nurses ran into the room.

10. The patient was weak and feeling tired.

Be careful with FOR and YET as these words can be used in different ways. In modern English they are not commonly used as conjunctions, and often sound out-dated in IELTS essays. 

Technology has helped rural families, for they can now buy products online.  ✘

Technology has helped rural families as they can now buy products online.  ✔︎

Technology has helped rural families because they can now buy products online.  ✔︎

Exercise One

Combine the independent clauses below. Decide if you need to use a comma, or if you can avoid one by removing repetition.

1. The child was crying. / Her mum picked her up.

2. The concert was cancelled at the last minute. / Everyone was given a full refund.

3. The teacher became angry. / She told the student to leave the room

4. The government has helped raise money. / It has also provided medical supplies

5. There is no time to stop the fire. / There is time to rescue the cat in the bedroom

6. We should send aid to affected countries. / This will mean they can feed the hungry.

7. The people in the city felt the new motorway was unnecessary. / They also said that pollution would get worse.

Exercise Two 

Look again at the example paragraph. Spend some time thinking about which sentences are simple sentences and which are compound sentences?

Cars cause a lot of pollution. Many cars are old and produce exhaust fumes. These cars should be banned, but people still drive them everyday. The government must make new laws. This will help to reduce pollution.

It is important to remember that simple and compound sentences are a normal part of spoken and written English. Test-takers should not try to avoid theses sentence types. Just be aware that only using them will lead to a poor score for grammar.

The next part of this series will explain how to use subordinating conjunctions and relative pronouns to create complex sentences.

ANSWERS