We use commas to make our sentences clear but it's also important to not overdo it. Sometimes a comma can be necessary in a sentence after an introductory phrase.
An introductory phrase is like a clause, but it doesn’t have its own subject and verb. We use it to stage the main part of the sentence. There are different types of introductory phrases, including prepositional phrases and appositive phrases.
A prepositional phrase is used to modify a verb or a noun and is a group of words consisting of a preposition, its object, and any other words that modify that object.
An appositive phrase follows another noun or noun phrase and provides information that further identifies or defines it. Appositive phrases can be restrictive and nonrestrictive.
Example
Explanation
While taking care of her dog, she felt better herself.
While taking care of her dog is a prepositional phrase separated by a comma.
Prepositional Phrases
Rule 1: When an introductory prepositional phrase is very short (less than four words), the comma is optional.
English
English
In the morning, we get up and brew our coffee.
The prepositional phrase (in the morning) has less than four words, so both options are acceptable.
Rule 2: If the introductory prepositional phrase is longer than four words, we use a comma.
Example
Explanation
After shopping for a few hours straight, she felt exhausted.
The prepositional phrase (after shopping for a few hours straight) is long, so we use a comma.
Appositive Phrases
Rule 3: We use commas to frame nonrestrictive appositive phrases, i.e., those providing nonessential information about the noun or the noun phrase.
Example
Explanation
Lucy, my childhood friend, is a big fan of Madonna.
We separated the appositive nonrestrictive phrase (my childhood friend), as it provides nonessential information. The sentence will still make sense without it.
Rule 4: We don't use commas with restrictive appositive phrases that provide essential information about the noun or the noun phrase.
Example
Explanation
My colleague Ellen doesn't drink coffee at all.
Here, the appositive is Ellen and it is a part of the essential information of my colleague, as we can assume that speaker has many colleagues but it's Ellen who doesn't drink coffee.
Quiz
1/4
Choose the correct punctuation. Before the cinema let's get some tacos.
0
correct answers.