Punctuation is essential when writing any text, whether it is a simple email or an essay. All of us have come across writing that has an excess of punctuation or a lack of it. Probably commas, periods, colons, semicolons, etcetera, were incorrectly used. If we learn to use punctuation marks appropriately, we will produce clear and enjoyable texts.
Commas are a good start when learning how to punctuate. And to do so, it is a good idea to review the basic types of sentences in English. The three basic types of sentences in English are simple sentences, compound sentences, and complex sentences. Let’s see the examples.
Vanessa bakes a cake in the morning.
Vanessa bakes a cake in the morning, and John eats it in the afternoon.
John has gained a lot of weight because of all the cake he eats.
As we can see, the simple sentence expresses one idea using the typical sentence construction with a subject, a verb, and an object. We say that this sentence contains a clause, with equates a clause with one sentence containing one idea alone.
Then we have the compound sentence. In it, we have two clauses or ideas united by the conjunction “and.” We can notice that each clause has a subject (Vanessa and John), and each one has a verb. When this situation happens, we separate both clauses using a comma. We can also see that each clause is independent. It means that we can take them apart in two simple sentences, and they do not lose their meaning.
Then we have the complex sentence. It has two clauses, but the second one depends on the first. It means that if we take them apart, the second one loses its meaning in the context of the idea expressed in the whole sentence. We also see that both clauses have a subject and verb, and they are joined by a connector. The connector is the word “because.”
When do we use commas in a simple sentence?
We usually use commas in simple sentences when we enumerate three or more items.
Liza has a big music collection. She has a lot of vinyl records, cassettes, and CDs.
In this example, there are three enumerated items: vinyl records, cassettes, and CDs. For that reason, we use commas. Please notice that we place a comma before “and” in this example. The last item has to be separated from the rest of the list.
Also notice that if we have only two items, we do not use any commas. We just use the conjunction between them.
I can eat liver or meat for lunch.
In this example, there is no need to separate “liver and meat” with a comma because there are only two elements.
What other conjunctions can we use in a simple sentence apart from “and.”
Some of the most common conjunctions are: but, or, nor, yet, so, for. There are many more conjunctions you can use.
As we said before, a compound sentence contains two clauses united by a conjunction, and each clause has a subject and a verb. Each clause is independent, and they could be separated into two independent, simple sentences if we wanted to.
An example could be:
Mondays are the most difficult days of the week, and Fridays are the happiest days.
When this situation occurs, we separate both clauses with a comma before the conjunction.
Is there a case in compound sentences where we do not use commas?
Yes. When the second clause of the sentence does not have its own subject, we do not use a comma to separate the two ideas.
John is eating a lot of fruit now and has lost a lot of weight.
Exercises with simple and compound sentences in English.
Now it will be your turn to use commas in simple and compound sentences. Identify each type of sentence and use commas if necessary. Put your answers in the comment section to have them reviewed.
- Berta loves taking her dog and cat for a walk in the morning.
- Volkswagen Audi and Mercedes Benz are german car brands.
- My cat eats meat chicken and cat food but he doesn’t eat fish.
- Whales make noises that are used in recordings as relaxation sounds.
- Some keyboard instruments are pianos organs and harpsichords.
- The internet existed before 1995 but it was not used in households yet.
- I have cooked a lot of chicken and fish this week and have used little oil with them
- Leonard trains at the gym five days a week so he is very lean now.
- Not my mother my aunt or my father speak Chinese.
- Mark trains at the gym and runs a lot in the park.
- I do not have either a car a bicycle or a motorbike.
- Elena leaves early from home so she doesn’t get to her office late.
- The nitrogenous bases in the ADN molecule are adenine guanine cytosine and thymine.
In the next article about this subject will continue with the study of punctuation for complex sentences and the other punctuation marks apart from commas.