Let’s take a look at several basic rules for using comma properly.

1. In lists

Commas are used to separate words and phrases when there are three or more of them.

Examples:

I will have a sandwich, an apple, an egg, and a bottle of milk for lunch.

The growing number of cars causes air pollution, noise pollution, and traffic problems.

2. Before coordinating conjunctions

Use commas before coordinating conjunctions such as and, but, or, and so in compound sentences.

Examples:

She did her best, but she failed the exam.

Many young adults can not afford the living expenses by their own, so they live with their parents to save money.

3. Separate multiple adjectives modifying the same noun

We use commas to separate a series of adjectives which modify the same noun.

Example: The tall, elegant lady is my boss.

4. After introductory adverbs, phrases, or clauses

Use commas after the following types of introductory adverbs or phrases.

• After introductory adverbs

Example: Surprisingly, most people believe that he is wrong.

• After transitional words

Example: Therefore, government should encourage those businesses to move to rural areas.

• After prepositional phrases

Example: In the past, it took much more time for people to travel outside the country.

• After participial phrases

Example: Walking on the beach, she found a beautiful seashell.

• After infinitive phrases

Example: To get a better job, you need to learn a specific skill.

• After dependent clauses (if they come before the independent clauses)

Example: If it rains tomorrow, I will stay at home.

• After words, such as “say” and before a quotation

Example: The famous scientist said, ” It is strange that only extraordinary men make the discoveries, which later appear so easy and simple.”

Commas are very common in English writing and there are more uses than the ones I have listed above. However, these are the most important for you to know. You should study these rules and practice writing example sentences of your own. When writing for the IELTS exam, you should ask yourself whether your sentences fall into the categories above, and thus whether you have included commas in the right place or not.

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