A comma is one of the most, if not the most, used prepositions in the English language. Knowing when not to use a comma is as important as knowing when to use it.
Let’s look at and understand all the 8 common comma mistakes that most people make.
1. Don’t use a comma to add two independent clauses.
Adding two sentences using a comma is the most common comma mistake we see students making. Here are some examples:
Examples:
- I love you, I can’t do this for you. ❌
- Janie and I went shopping yesterday, we bought a lot of toys and sweets for the kids. ❌
- Max didn’t join us, he was feeling blue. ❌
Corrections:-
a) Use a coordinating conjunction.
Coordinating conjunctions: for, and, nor, but, or, yet, so (FANBOYS)
- I love you, but I can’t do this for you.
- Janie and I went shopping yesterday, and we bought a lot of toys and sweets for the kids.
- Max didn’t join us, for he was feeling blue.
b) Use a semicolon if both sentences are closely related.
- Janie and I went shopping yesterday; we bought a lot of toys and sweets for the kids.
- Max didn’t join us; he was feeling blue.
c) Use a colon if the second sentence explains, justifies, or summarizes the first one.
- Max didn’t join us: he was feeling blue.
d) Use a period (Full stop) and separate the sentences.
- I love you. I can’t do this for you.
- Janie and I went shopping yesterday. We bought a lot of toys and sweets for the kids.
- Max didn’t join us. He was feeling blue.
2. Don’t use a comma to separate a subject from a predicate.
Students often make the mistake of using a comma right after the subject to make a distinction between the subject and the predicate.
It is generally done when the subject is quite long and readers might have difficulty finding the subject. Irrespective of the length of the subject, you should never set it off using a comma.
Examples:
- Your friend Jacob, is a smart businessman. ❌
Correction: Your friend Jacob is a smart businessman. ✔️
- The man standing next to the car colored black and blue, is a magician. ❌
Correction: The man standing next to the car colored black and blue is a magician. ✔️
- The history of his training sessions taken at places where anyone can come and be a part of them, is something that should make a movie about. ❌
Correction: The history of his training sessions taken at places where anyone can come and be a part of them is something that should make a movie about. ✔️
3. Don’t use a comma to set off essential information.
Modifiers in the form of essential adjective clauses, prepositional phrases, infinitive phrases, and appositive phrases provide essential (important) information in a sentence. We mustn’t offset these using a comma.
Examples:-
- Your friend, Rohan, looks really passionate to me. ❌
(The noun Rohan is identifying the noun phrase ‘your friend’ and giving essential information about it. You might have many friends; ‘Rohan’ helps us identify which friend the speaker is referring to. It shouldn’t be offset using commas.)
Correction: Your friend Rohan looks really passionate to me. ✔️
- The man, who called me last night is a gangster. ❌
(‘Who called me last night’ is an essential adjective clause, which is telling us which man the speaker is talking about. Therefore, there shouldn’t be a comma between the noun and its modifier.)
Correction: The man who called me last night is a gangster.✔️
- Could you pass the book, under your bag? ❌
(‘Under your bag’ is a prepositional phrase that’s identifying ‘the book’ and making it specific. Therefore, we shouldn’t use a comma after the noun phrase ‘the book’.)
Correction: Could you pass the book under your bag? ✔️
- Alan left the job, to pursue his passion of teaching. ❌
(”To pursue his passion of teaching’ is an Infinitive phrase that’s modifying the main verb and talking about its reason. We shouldn’t use a comma to offset it here.)
Correction: Alan left the job to pursue his passion of teaching. ✔️
Note that if a sentence starts with an Infinitive phrase, we use a comma right after it.
- To pursue his passion of teaching, Alan left his job.
4. Don’t use a comma between a compound subject (two subjects) and compound objects (two objects).
Using a comma in a compound subject or a compound predicate to separate it is another common comma mistake.
Examples:
- Jon, and his training partners have black belts in Jiu-Jitsu. ❌
- His attitude before the fight, and his attitude after the fight were not the same. ❌
- I love teaching English, and writing poems. ❌
- We are not talking about Jon, and Max. ❌
Corrections:
- Jon and his training partners have black belts in Jiu Jitsu.
- His attitude before the fight and his attitude after the fight were not the same.
- I love teaching English and writing poems.
- We are not talking about Jon and Max.
Note that if you add three or more items to a list of nouns/verbs, it’s advised to use a comma before the last item. This comma is termed an Oxford comma.
- I love eating pasta, bread and butter. (Here, ‘bread and butter’ is one food item.)
The list of what I love eating has two items:
- Pasta
- Bread and butter (one dish)
Using an Oxford comma before the last item will make it clear that the following item is separate.
- I love eating pasta, bread, and butter. (The last comma, Oxford comma, indicates that ‘bread’ and ‘butter’ are two separate items here.)
5. Don’t use a comma to add two verbs or verb phrases in a compound predicate.
- He opened the box, and started crying. ❌
- As soon as the train arrived, we packed the bags, and left the station. ❌
Corrections:-
- He opened the box and started crying.
- As soon as the train arrived, we packed the bags and left the station.
Note that if the second verb phrase in the compound predicate can confuse readers, you can use a comma.
- Alex found the man who killed a dog and beat him relentlessly.
Now, think! Is it Alex who beat him (who?) relentlessly or the man? To avoid the confusion, we can use a comma after the first predicate (verb phrase).
- Alex found the man who killed a dog, and beat him relentlessly
Now it’s clear that Alex did two actions:
- Found the man who killed a dog.
- Beat him (the man) relentlessly.
6. Don’t use a comma to separate a verb from its object or complement.
- What I really want to do is, to pack my bag and explore the country. ❌
- The most important thing to learn about time is, that it doesn’t wait for anyone. ❌
- No-one knows, what he wants. ❌
Corrections:
- What I really want to do is to pack my bag and explore the country.
- The most important thing to learn about time is that it doesn’t wait for anyone.
- No-one knows what he wants.
7. Don’t use a comma to separate an independent clause from a dependent clause if the independent clause is coming before the dependent clause.
Dependent clause + comma + independent clause
Independent clause + dependent clause
- We will leave the place, when the rain stops. ❌
Correction:
- We will leave the place when the rain stops.
or - When the rain stops, we will leave the place.
8. Don’t use a comma before the conjunction ‘OR’ unless it adds two independent clauses.
- London, or Paris is great for a wedding destination. ❌
- We can have some hot coffee, or some cold ice tea. ❌
Corrections:
- London or Paris is great for a wedding destination.
- We can have some hot coffee or some cold ice tea.
Note that if ‘or’ adds two independent clauses, we must use a comma before it.
- You accept my offer, or you can leave.
Hope you enjoyed the lesson. Feel free to share your question, doubt, or feedback in the comment section, and also, share the post with the people that need it.
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